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diff --git a/i/pc104/initrd/conf/busybox/shell/hush.c b/i/pc104/initrd/conf/busybox/shell/hush.c
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+++ b/i/pc104/initrd/conf/busybox/shell/hush.c
@@ -0,0 +1,2928 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * sh.c -- a prototype Bourne shell grammar parser
+ * Intended to follow the original Thompson and Ritchie
+ * "small and simple is beautiful" philosophy, which
+ * incidentally is a good match to today's BusyBox.
+ *
+ * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org>
+ *
+ * Credits:
+ * The parser routines proper are all original material, first
+ * written Dec 2000 and Jan 2001 by Larry Doolittle. The
+ * execution engine, the builtins, and much of the underlying
+ * support has been adapted from busybox-0.49pre's lash, which is
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ * written by Erik Andersen <andersen@codepoet.org>. That, in turn,
+ * is based in part on ladsh.c, by Michael K. Johnson and Erik W.
+ * Troan, which they placed in the public domain. I don't know
+ * how much of the Johnson/Troan code has survived the repeated
+ * rewrites.
+ *
+ * Other credits:
+ * simple_itoa() was lifted from boa-0.93.15
+ * b_addchr() derived from similar w_addchar function in glibc-2.2
+ * setup_redirect(), redirect_opt_num(), and big chunks of main()
+ * and many builtins derived from contributions by Erik Andersen
+ * miscellaneous bugfixes from Matt Kraai
+ *
+ * There are two big (and related) architecture differences between
+ * this parser and the lash parser. One is that this version is
+ * actually designed from the ground up to understand nearly all
+ * of the Bourne grammar. The second, consequential change is that
+ * the parser and input reader have been turned inside out. Now,
+ * the parser is in control, and asks for input as needed. The old
+ * way had the input reader in control, and it asked for parsing to
+ * take place as needed. The new way makes it much easier to properly
+ * handle the recursion implicit in the various substitutions, especially
+ * across continuation lines.
+ *
+ * Bash grammar not implemented: (how many of these were in original sh?)
+ * $@ (those sure look like weird quoting rules)
+ * $_
+ * ! negation operator for pipes
+ * &> and >& redirection of stdout+stderr
+ * Brace Expansion
+ * Tilde Expansion
+ * fancy forms of Parameter Expansion
+ * aliases
+ * Arithmetic Expansion
+ * <(list) and >(list) Process Substitution
+ * reserved words: case, esac, select, function
+ * Here Documents ( << word )
+ * Functions
+ * Major bugs:
+ * job handling woefully incomplete and buggy
+ * reserved word execution woefully incomplete and buggy
+ * to-do:
+ * port selected bugfixes from post-0.49 busybox lash - done?
+ * finish implementing reserved words: for, while, until, do, done
+ * change { and } from special chars to reserved words
+ * builtins: break, continue, eval, return, set, trap, ulimit
+ * test magic exec
+ * handle children going into background
+ * clean up recognition of null pipes
+ * check setting of global_argc and global_argv
+ * control-C handling, probably with longjmp
+ * follow IFS rules more precisely, including update semantics
+ * figure out what to do with backslash-newline
+ * explain why we use signal instead of sigaction
+ * propagate syntax errors, die on resource errors?
+ * continuation lines, both explicit and implicit - done?
+ * memory leak finding and plugging - done?
+ * more testing, especially quoting rules and redirection
+ * document how quoting rules not precisely followed for variable assignments
+ * maybe change map[] to use 2-bit entries
+ * (eventually) remove all the printf's
+ *
+ * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ */
+
+#include "busybox.h"
+#include <glob.h> /* glob, of course */
+#include <getopt.h> /* should be pretty obvious */
+
+//#include <sys/wait.h>
+//#include <signal.h>
+
+/* #include <dmalloc.h> */
+/* #define DEBUG_SHELL */
+
+
+#define SPECIAL_VAR_SYMBOL 03
+#define FLAG_EXIT_FROM_LOOP 1
+#define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
+#define FLAG_REPARSING (1 << 2) /* >=2nd pass */
+
+typedef enum {
+ REDIRECT_INPUT = 1,
+ REDIRECT_OVERWRITE = 2,
+ REDIRECT_APPEND = 3,
+ REDIRECT_HEREIS = 4,
+ REDIRECT_IO = 5
+} redir_type;
+
+/* The descrip member of this structure is only used to make debugging
+ * output pretty */
+static const struct {int mode; int default_fd; const char *descrip;} redir_table[] = {
+ { 0, 0, "()" },
+ { O_RDONLY, 0, "<" },
+ { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
+ { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
+ { O_RDONLY, -1, "<<" },
+ { O_RDWR, 1, "<>" }
+};
+
+typedef enum {
+ PIPE_SEQ = 1,
+ PIPE_AND = 2,
+ PIPE_OR = 3,
+ PIPE_BG = 4,
+} pipe_style;
+
+/* might eventually control execution */
+typedef enum {
+ RES_NONE = 0,
+ RES_IF = 1,
+ RES_THEN = 2,
+ RES_ELIF = 3,
+ RES_ELSE = 4,
+ RES_FI = 5,
+ RES_FOR = 6,
+ RES_WHILE = 7,
+ RES_UNTIL = 8,
+ RES_DO = 9,
+ RES_DONE = 10,
+ RES_XXXX = 11,
+ RES_IN = 12,
+ RES_SNTX = 13
+} reserved_style;
+#define FLAG_END (1<<RES_NONE)
+#define FLAG_IF (1<<RES_IF)
+#define FLAG_THEN (1<<RES_THEN)
+#define FLAG_ELIF (1<<RES_ELIF)
+#define FLAG_ELSE (1<<RES_ELSE)
+#define FLAG_FI (1<<RES_FI)
+#define FLAG_FOR (1<<RES_FOR)
+#define FLAG_WHILE (1<<RES_WHILE)
+#define FLAG_UNTIL (1<<RES_UNTIL)
+#define FLAG_DO (1<<RES_DO)
+#define FLAG_DONE (1<<RES_DONE)
+#define FLAG_IN (1<<RES_IN)
+#define FLAG_START (1<<RES_XXXX)
+
+/* This holds pointers to the various results of parsing */
+struct p_context {
+ struct child_prog *child;
+ struct pipe *list_head;
+ struct pipe *pipe;
+ struct redir_struct *pending_redirect;
+ reserved_style w;
+ int old_flag; /* for figuring out valid reserved words */
+ struct p_context *stack;
+ int type; /* define type of parser : ";$" common or special symbol */
+ /* How about quoting status? */
+};
+
+struct redir_struct {
+ redir_type type; /* type of redirection */
+ int fd; /* file descriptor being redirected */
+ int dup; /* -1, or file descriptor being duplicated */
+ struct redir_struct *next; /* pointer to the next redirect in the list */
+ glob_t word; /* *word.gl_pathv is the filename */
+};
+
+struct child_prog {
+ pid_t pid; /* 0 if exited */
+ char **argv; /* program name and arguments */
+ struct pipe *group; /* if non-NULL, first in group or subshell */
+ int subshell; /* flag, non-zero if group must be forked */
+ struct redir_struct *redirects; /* I/O redirections */
+ glob_t glob_result; /* result of parameter globbing */
+ int is_stopped; /* is the program currently running? */
+ struct pipe *family; /* pointer back to the child's parent pipe */
+ int sp; /* number of SPECIAL_VAR_SYMBOL */
+ int type;
+};
+
+struct pipe {
+ int jobid; /* job number */
+ int num_progs; /* total number of programs in job */
+ int running_progs; /* number of programs running */
+ char *text; /* name of job */
+ char *cmdbuf; /* buffer various argv's point into */
+ pid_t pgrp; /* process group ID for the job */
+ struct child_prog *progs; /* array of commands in pipe */
+ struct pipe *next; /* to track background commands */
+ int stopped_progs; /* number of programs alive, but stopped */
+ int job_context; /* bitmask defining current context */
+ pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
+ reserved_style r_mode; /* supports if, for, while, until */
+};
+
+struct close_me {
+ int fd;
+ struct close_me *next;
+};
+
+struct variables {
+ const char *name;
+ const char *value;
+ int flg_export;
+ int flg_read_only;
+ struct variables *next;
+};
+
+/* globals, connect us to the outside world
+ * the first three support $?, $#, and $1 */
+static char **global_argv;
+static int global_argc;
+static int last_return_code;
+extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
+
+/* "globals" within this file */
+static const char *ifs;
+static unsigned char map[256];
+static int fake_mode;
+static int interactive;
+static struct close_me *close_me_head;
+static const char *cwd;
+static struct pipe *job_list;
+static unsigned last_bg_pid;
+static int last_jobid;
+static unsigned shell_terminal;
+static const char *PS1;
+static const char *PS2;
+static struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
+static struct variables *top_vars = &shell_ver;
+
+
+#define B_CHUNK (100)
+#define B_NOSPAC 1
+
+typedef struct {
+ char *data;
+ int length;
+ int maxlen;
+ int quote;
+ int nonnull;
+} o_string;
+#define NULL_O_STRING {NULL,0,0,0,0}
+/* used for initialization:
+ o_string foo = NULL_O_STRING; */
+
+/* I can almost use ordinary FILE *. Is open_memstream() universally
+ * available? Where is it documented? */
+struct in_str {
+ const char *p;
+ char peek_buf[2];
+ int __promptme;
+ int promptmode;
+ FILE *file;
+ int (*get) (struct in_str *);
+ int (*peek) (struct in_str *);
+};
+#define b_getch(input) ((input)->get(input))
+#define b_peek(input) ((input)->peek(input))
+
+#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
+
+struct built_in_command {
+ const char *cmd; /* name */
+ const char *descr; /* description */
+ int (*function) (struct child_prog *); /* function ptr */
+};
+
+/* belongs in busybox.h */
+static int max(int a, int b)
+{
+ return (a>b)?a:b;
+}
+
+/* This should be in utility.c */
+#ifdef DEBUG_SHELL
+static void debug_printf(const char *format, ...)
+{
+ va_list args;
+ va_start(args, format);
+ vfprintf(stderr, format, args);
+ va_end(args);
+}
+/* broken, of course, but OK for testing */
+static char *indenter(int i)
+{
+ static char blanks[] = " ";
+ return &blanks[sizeof(blanks)-i-1];
+}
+#else
+#define debug_printf(...) do {;} while (0);
+#endif
+#define final_printf debug_printf
+
+static void __syntax(const char *file, int line)
+{
+ bb_error_msg("syntax error %s:%d", file, line);
+}
+// NB: was __FILE__, but that produces full path sometimess, so...
+#define syntax() __syntax("hush.c", __LINE__)
+
+/* Index of subroutines: */
+/* function prototypes for builtins */
+static int builtin_cd(struct child_prog *child);
+static int builtin_env(struct child_prog *child);
+static int builtin_eval(struct child_prog *child);
+static int builtin_exec(struct child_prog *child);
+static int builtin_exit(struct child_prog *child);
+static int builtin_export(struct child_prog *child);
+static int builtin_fg_bg(struct child_prog *child);
+static int builtin_help(struct child_prog *child);
+static int builtin_jobs(struct child_prog *child);
+static int builtin_pwd(struct child_prog *child);
+static int builtin_read(struct child_prog *child);
+static int builtin_set(struct child_prog *child);
+static int builtin_shift(struct child_prog *child);
+static int builtin_source(struct child_prog *child);
+static int builtin_umask(struct child_prog *child);
+static int builtin_unset(struct child_prog *child);
+static int builtin_not_written(struct child_prog *child);
+/* o_string manipulation: */
+static int b_check_space(o_string *o, int len);
+static int b_addchr(o_string *o, int ch);
+static void b_reset(o_string *o);
+static int b_addqchr(o_string *o, int ch, int quote);
+static int b_adduint(o_string *o, unsigned i);
+/* in_str manipulations: */
+static int static_get(struct in_str *i);
+static int static_peek(struct in_str *i);
+static int file_get(struct in_str *i);
+static int file_peek(struct in_str *i);
+static void setup_file_in_str(struct in_str *i, FILE *f);
+static void setup_string_in_str(struct in_str *i, const char *s);
+/* close_me manipulations: */
+static void mark_open(int fd);
+static void mark_closed(int fd);
+static void close_all(void);
+/* "run" the final data structures: */
+static int free_pipe_list(struct pipe *head, int indent);
+static int free_pipe(struct pipe *pi, int indent);
+/* really run the final data structures: */
+static int setup_redirects(struct child_prog *prog, int squirrel[]);
+static int run_list_real(struct pipe *pi);
+static void pseudo_exec(struct child_prog *child) ATTRIBUTE_NORETURN;
+static int run_pipe_real(struct pipe *pi);
+/* extended glob support: */
+static int globhack(const char *src, int flags, glob_t *pglob);
+static int glob_needed(const char *s);
+static int xglob(o_string *dest, int flags, glob_t *pglob);
+/* variable assignment: */
+static int is_assignment(const char *s);
+/* data structure manipulation: */
+static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
+static void initialize_context(struct p_context *ctx);
+static int done_word(o_string *dest, struct p_context *ctx);
+static int done_command(struct p_context *ctx);
+static int done_pipe(struct p_context *ctx, pipe_style type);
+/* primary string parsing: */
+static int redirect_dup_num(struct in_str *input);
+static int redirect_opt_num(o_string *o);
+static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end);
+static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
+static const char *lookup_param(const char *src);
+static char *make_string(char **inp);
+static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
+static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
+static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger);
+/* setup: */
+static int parse_stream_outer(struct in_str *inp, int flag);
+static int parse_string_outer(const char *s, int flag);
+static int parse_file_outer(FILE *f);
+/* job management: */
+static int checkjobs(struct pipe* fg_pipe);
+static void insert_bg_job(struct pipe *pi);
+static void remove_bg_job(struct pipe *pi);
+/* local variable support */
+static char **make_list_in(char **inp, char *name);
+static char *insert_var_value(char *inp);
+static const char *get_local_var(const char *var);
+static void unset_local_var(const char *name);
+static int set_local_var(const char *s, int flg_export);
+
+/* Table of built-in functions. They can be forked or not, depending on
+ * context: within pipes, they fork. As simple commands, they do not.
+ * When used in non-forking context, they can change global variables
+ * in the parent shell process. If forked, of course they cannot.
+ * For example, 'unset foo | whatever' will parse and run, but foo will
+ * still be set at the end. */
+static const struct built_in_command bltins[] = {
+ { "bg", "Resume a job in the background", builtin_fg_bg },
+ { "break", "Exit for, while or until loop", builtin_not_written },
+ { "cd", "Change working directory", builtin_cd },
+ { "continue", "Continue for, while or until loop", builtin_not_written },
+ { "env", "Print all environment variables", builtin_env },
+ { "eval", "Construct and run shell command", builtin_eval },
+ { "exec", "Exec command, replacing this shell with the exec'd process",
+ builtin_exec },
+ { "exit", "Exit from shell()", builtin_exit },
+ { "export", "Set environment variable", builtin_export },
+ { "fg", "Bring job into the foreground", builtin_fg_bg },
+ { "jobs", "Lists the active jobs", builtin_jobs },
+ { "pwd", "Print current directory", builtin_pwd },
+ { "read", "Input environment variable", builtin_read },
+ { "return", "Return from a function", builtin_not_written },
+ { "set", "Set/unset shell local variables", builtin_set },
+ { "shift", "Shift positional parameters", builtin_shift },
+ { "trap", "Trap signals", builtin_not_written },
+ { "ulimit","Controls resource limits", builtin_not_written },
+ { "umask","Sets file creation mask", builtin_umask },
+ { "unset", "Unset environment variable", builtin_unset },
+ { ".", "Source-in and run commands in a file", builtin_source },
+ { "help", "List shell built-in commands", builtin_help },
+ { NULL, NULL, NULL }
+};
+
+static const char *set_cwd(void)
+{
+ if (cwd == bb_msg_unknown)
+ cwd = NULL; /* xrealloc_getcwd_or_warn(arg) called free(arg) */
+ cwd = xrealloc_getcwd_or_warn((char *)cwd);
+ if (!cwd)
+ cwd = bb_msg_unknown;
+ return cwd;
+}
+
+/* built-in 'eval' handler */
+static int builtin_eval(struct child_prog *child)
+{
+ char *str = NULL;
+ int rcode = EXIT_SUCCESS;
+
+ if (child->argv[1]) {
+ str = make_string(child->argv + 1);
+ parse_string_outer(str, FLAG_EXIT_FROM_LOOP |
+ FLAG_PARSE_SEMICOLON);
+ free(str);
+ rcode = last_return_code;
+ }
+ return rcode;
+}
+
+/* built-in 'cd <path>' handler */
+static int builtin_cd(struct child_prog *child)
+{
+ char *newdir;
+ if (child->argv[1] == NULL)
+ newdir = getenv("HOME");
+ else
+ newdir = child->argv[1];
+ if (chdir(newdir)) {
+ printf("cd: %s: %s\n", newdir, strerror(errno));
+ return EXIT_FAILURE;
+ }
+ set_cwd();
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'env' handler */
+static int builtin_env(struct child_prog *dummy ATTRIBUTE_UNUSED)
+{
+ char **e = environ;
+ if (e == NULL)
+ return EXIT_FAILURE;
+ while (*e) {
+ puts(*e++);
+ }
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'exec' handler */
+static int builtin_exec(struct child_prog *child)
+{
+ if (child->argv[1] == NULL)
+ return EXIT_SUCCESS; /* Really? */
+ child->argv++;
+ pseudo_exec(child);
+ /* never returns */
+}
+
+/* built-in 'exit' handler */
+static int builtin_exit(struct child_prog *child)
+{
+ if (child->argv[1] == NULL)
+ exit(last_return_code);
+ exit (atoi(child->argv[1]));
+}
+
+/* built-in 'export VAR=value' handler */
+static int builtin_export(struct child_prog *child)
+{
+ int res = 0;
+ char *name = child->argv[1];
+
+ if (name == NULL) {
+ return builtin_env(child);
+ }
+
+ name = strdup(name);
+
+ if (name) {
+ const char *value = strchr(name, '=');
+
+ if (!value) {
+ char *tmp;
+ /* They are exporting something without an =VALUE */
+
+ value = get_local_var(name);
+ if (value) {
+ size_t ln = strlen(name);
+
+ tmp = realloc(name, ln+strlen(value)+2);
+ if (tmp == NULL)
+ res = -1;
+ else {
+ sprintf(tmp+ln, "=%s", value);
+ name = tmp;
+ }
+ } else {
+ /* bash does not return an error when trying to export
+ * an undefined variable. Do likewise. */
+ res = 1;
+ }
+ }
+ }
+ if (res < 0)
+ bb_perror_msg("export");
+ else if (res == 0)
+ res = set_local_var(name, 1);
+ else
+ res = 0;
+ free(name);
+ return res;
+}
+
+/* built-in 'fg' and 'bg' handler */
+static int builtin_fg_bg(struct child_prog *child)
+{
+ int i, jobnum;
+ struct pipe *pi = NULL;
+
+ if (!interactive)
+ return EXIT_FAILURE;
+ /* If they gave us no args, assume they want the last backgrounded task */
+ if (!child->argv[1]) {
+ for (pi = job_list; pi; pi = pi->next) {
+ if (pi->jobid == last_jobid) {
+ break;
+ }
+ }
+ if (!pi) {
+ bb_error_msg("%s: no current job", child->argv[0]);
+ return EXIT_FAILURE;
+ }
+ } else {
+ if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) {
+ bb_error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]);
+ return EXIT_FAILURE;
+ }
+ for (pi = job_list; pi; pi = pi->next) {
+ if (pi->jobid == jobnum) {
+ break;
+ }
+ }
+ if (!pi) {
+ bb_error_msg("%s: %d: no such job", child->argv[0], jobnum);
+ return EXIT_FAILURE;
+ }
+ }
+
+ if (*child->argv[0] == 'f') {
+ /* Put the job into the foreground. */
+ tcsetpgrp(shell_terminal, pi->pgrp);
+ }
+
+ /* Restart the processes in the job */
+ for (i = 0; i < pi->num_progs; i++)
+ pi->progs[i].is_stopped = 0;
+
+ i = kill(- pi->pgrp, SIGCONT);
+ if (i < 0) {
+ if (i == ESRCH) {
+ remove_bg_job(pi);
+ } else {
+ bb_perror_msg("kill (SIGCONT)");
+ }
+ }
+
+ pi->stopped_progs = 0;
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'help' handler */
+static int builtin_help(struct child_prog *dummy ATTRIBUTE_UNUSED)
+{
+ const struct built_in_command *x;
+
+ printf("\nBuilt-in commands:\n");
+ printf("-------------------\n");
+ for (x = bltins; x->cmd; x++) {
+ if (x->descr == NULL)
+ continue;
+ printf("%s\t%s\n", x->cmd, x->descr);
+ }
+ printf("\n\n");
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'jobs' handler */
+static int builtin_jobs(struct child_prog *child ATTRIBUTE_UNUSED)
+{
+ struct pipe *job;
+ const char *status_string;
+
+ for (job = job_list; job; job = job->next) {
+ if (job->running_progs == job->stopped_progs)
+ status_string = "Stopped";
+ else
+ status_string = "Running";
+
+ printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->text);
+ }
+ return EXIT_SUCCESS;
+}
+
+
+/* built-in 'pwd' handler */
+static int builtin_pwd(struct child_prog *dummy ATTRIBUTE_UNUSED)
+{
+ puts(set_cwd());
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'read VAR' handler */
+static int builtin_read(struct child_prog *child)
+{
+ int res;
+
+ if (child->argv[1]) {
+ char string[BUFSIZ];
+ char *var = NULL;
+
+ string[0] = '\0'; /* In case stdin has only EOF */
+ /* read string */
+ fgets(string, sizeof(string), stdin);
+ chomp(string);
+ var = malloc(strlen(child->argv[1]) + strlen(string) + 2);
+ if (var) {
+ sprintf(var, "%s=%s", child->argv[1], string);
+ res = set_local_var(var, 0);
+ } else
+ res = -1;
+ if (res)
+ bb_perror_msg("read");
+ free(var); /* So not move up to avoid breaking errno */
+ return res;
+ }
+ do res = getchar(); while (res != '\n' && res != EOF);
+ return 0;
+}
+
+/* built-in 'set VAR=value' handler */
+static int builtin_set(struct child_prog *child)
+{
+ char *temp = child->argv[1];
+ struct variables *e;
+
+ if (temp == NULL)
+ for (e = top_vars; e; e = e->next)
+ printf("%s=%s\n", e->name, e->value);
+ else
+ set_local_var(temp, 0);
+
+ return EXIT_SUCCESS;
+}
+
+
+/* Built-in 'shift' handler */
+static int builtin_shift(struct child_prog *child)
+{
+ int n = 1;
+ if (child->argv[1]) {
+ n = atoi(child->argv[1]);
+ }
+ if (n >= 0 && n < global_argc) {
+ /* XXX This probably breaks $0 */
+ global_argc -= n;
+ global_argv += n;
+ return EXIT_SUCCESS;
+ } else {
+ return EXIT_FAILURE;
+ }
+}
+
+/* Built-in '.' handler (read-in and execute commands from file) */
+static int builtin_source(struct child_prog *child)
+{
+ FILE *input;
+ int status;
+
+ if (child->argv[1] == NULL)
+ return EXIT_FAILURE;
+
+ /* XXX search through $PATH is missing */
+ input = fopen(child->argv[1], "r");
+ if (!input) {
+ bb_error_msg("cannot open '%s'", child->argv[1]);
+ return EXIT_FAILURE;
+ }
+
+ /* Now run the file */
+ /* XXX argv and argc are broken; need to save old global_argv
+ * (pointer only is OK!) on this stack frame,
+ * set global_argv=child->argv+1, recurse, and restore. */
+ mark_open(fileno(input));
+ status = parse_file_outer(input);
+ mark_closed(fileno(input));
+ fclose(input);
+ return status;
+}
+
+static int builtin_umask(struct child_prog *child)
+{
+ mode_t new_umask;
+ const char *arg = child->argv[1];
+ char *end;
+ if (arg) {
+ new_umask = strtoul(arg, &end, 8);
+ if (*end != '\0' || end == arg) {
+ return EXIT_FAILURE;
+ }
+ } else {
+ new_umask = umask(0);
+ printf("%.3o\n", (unsigned) new_umask);
+ }
+ umask(new_umask);
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'unset VAR' handler */
+static int builtin_unset(struct child_prog *child)
+{
+ /* bash returned already true */
+ unset_local_var(child->argv[1]);
+ return EXIT_SUCCESS;
+}
+
+static int builtin_not_written(struct child_prog *child)
+{
+ printf("builtin_%s not written\n", child->argv[0]);
+ return EXIT_FAILURE;
+}
+
+static int b_check_space(o_string *o, int len)
+{
+ /* It would be easy to drop a more restrictive policy
+ * in here, such as setting a maximum string length */
+ if (o->length + len > o->maxlen) {
+ char *old_data = o->data;
+ /* assert (data == NULL || o->maxlen != 0); */
+ o->maxlen += max(2*len, B_CHUNK);
+ o->data = realloc(o->data, 1 + o->maxlen);
+ if (o->data == NULL) {
+ free(old_data);
+ }
+ }
+ return o->data == NULL;
+}
+
+static int b_addchr(o_string *o, int ch)
+{
+ debug_printf("b_addchr: %c %d %p\n", ch, o->length, o);
+ if (b_check_space(o, 1))
+ return B_NOSPAC;
+ o->data[o->length] = ch;
+ o->length++;
+ o->data[o->length] = '\0';
+ return 0;
+}
+
+static void b_reset(o_string *o)
+{
+ o->length = 0;
+ o->nonnull = 0;
+ if (o->data != NULL)
+ *o->data = '\0';
+}
+
+static void b_free(o_string *o)
+{
+ b_reset(o);
+ free(o->data);
+ o->data = NULL;
+ o->maxlen = 0;
+}
+
+/* My analysis of quoting semantics tells me that state information
+ * is associated with a destination, not a source.
+ */
+static int b_addqchr(o_string *o, int ch, int quote)
+{
+ if (quote && strchr("*?[\\",ch)) {
+ int rc;
+ rc = b_addchr(o, '\\');
+ if (rc)
+ return rc;
+ }
+ return b_addchr(o, ch);
+}
+
+/* belongs in utility.c */
+static char *simple_itoa(unsigned i)
+{
+ static char local[sizeof(int)*3 + 2];
+ char *p = &local[sizeof(int)*3 + 2 - 1];
+ *p-- = '\0';
+ do {
+ *p-- = '0' + i % 10;
+ i /= 10;
+ } while (i > 0);
+ return p + 1;
+}
+
+static int b_adduint(o_string *o, unsigned i)
+{
+ int r;
+ char *p = simple_itoa(i);
+ /* no escape checking necessary */
+ do r = b_addchr(o, *p++); while (r == 0 && *p);
+ return r;
+}
+
+static int static_get(struct in_str *i)
+{
+ int ch = *i->p++;
+ if (ch == '\0') return EOF;
+ return ch;
+}
+
+static int static_peek(struct in_str *i)
+{
+ return *i->p;
+}
+
+static void cmdedit_set_initial_prompt(void)
+{
+#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
+ PS1 = NULL;
+#else
+ PS1 = getenv("PS1");
+ if (PS1 == NULL)
+ PS1 = "\\w \\$ ";
+#endif
+}
+
+static const char* setup_prompt_string(int promptmode)
+{
+ const char *prompt_str;
+ debug_printf("setup_prompt_string %d ", promptmode);
+#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
+ /* Set up the prompt */
+ if (promptmode == 1) {
+ char *ns;
+ free((char*)PS1);
+ ns = xmalloc(strlen(cwd)+4);
+ sprintf(ns, "%s %s", cwd, (geteuid() != 0) ? "$ " : "# ");
+ prompt_str = ns;
+ PS1 = ns;
+ } else {
+ prompt_str = PS2;
+ }
+#else
+ prompt_str = (promptmode == 1) ? PS1 : PS2;
+#endif
+ debug_printf("result %s\n", prompt_str);
+ return prompt_str;
+}
+
+#if ENABLE_FEATURE_EDITING
+static line_input_t *line_input_state;
+#endif
+
+static void get_user_input(struct in_str *i)
+{
+ const char *prompt_str;
+ static char the_command[BUFSIZ];
+
+ prompt_str = setup_prompt_string(i->promptmode);
+#if ENABLE_FEATURE_EDITING
+ /*
+ ** enable command line editing only while a command line
+ ** is actually being read; otherwise, we'll end up bequeathing
+ ** atexit() handlers and other unwanted stuff to our
+ ** child processes (rob@sysgo.de)
+ */
+ read_line_input(prompt_str, the_command, BUFSIZ, line_input_state);
+#else
+ fputs(prompt_str, stdout);
+ fflush(stdout);
+ the_command[0] = fgetc(i->file);
+ the_command[1] = '\0';
+#endif
+ fflush(stdout);
+ i->p = the_command;
+}
+
+/* This is the magic location that prints prompts
+ * and gets data back from the user */
+static int file_get(struct in_str *i)
+{
+ int ch;
+
+ ch = 0;
+ /* If there is data waiting, eat it up */
+ if (i->p && *i->p) {
+ ch = *i->p++;
+ } else {
+ /* need to double check i->file because we might be doing something
+ * more complicated by now, like sourcing or substituting. */
+ if (i->__promptme && interactive && i->file == stdin) {
+ while (!i->p || !(interactive && strlen(i->p))) {
+ get_user_input(i);
+ }
+ i->promptmode = 2;
+ i->__promptme = 0;
+ if (i->p && *i->p) {
+ ch = *i->p++;
+ }
+ } else {
+ ch = fgetc(i->file);
+ }
+
+ debug_printf("b_getch: got a %d\n", ch);
+ }
+ if (ch == '\n')
+ i->__promptme = 1;
+ return ch;
+}
+
+/* All the callers guarantee this routine will never be
+ * used right after a newline, so prompting is not needed.
+ */
+static int file_peek(struct in_str *i)
+{
+ if (i->p && *i->p) {
+ return *i->p;
+ } else {
+ i->peek_buf[0] = fgetc(i->file);
+ i->peek_buf[1] = '\0';
+ i->p = i->peek_buf;
+ debug_printf("b_peek: got a %d\n", *i->p);
+ return *i->p;
+ }
+}
+
+static void setup_file_in_str(struct in_str *i, FILE *f)
+{
+ i->peek = file_peek;
+ i->get = file_get;
+ i->__promptme = 1;
+ i->promptmode = 1;
+ i->file = f;
+ i->p = NULL;
+}
+
+static void setup_string_in_str(struct in_str *i, const char *s)
+{
+ i->peek = static_peek;
+ i->get = static_get;
+ i->__promptme = 1;
+ i->promptmode = 1;
+ i->p = s;
+}
+
+static void mark_open(int fd)
+{
+ struct close_me *new = xmalloc(sizeof(struct close_me));
+ new->fd = fd;
+ new->next = close_me_head;
+ close_me_head = new;
+}
+
+static void mark_closed(int fd)
+{
+ struct close_me *tmp;
+ if (close_me_head == NULL || close_me_head->fd != fd)
+ bb_error_msg_and_die("corrupt close_me");
+ tmp = close_me_head;
+ close_me_head = close_me_head->next;
+ free(tmp);
+}
+
+static void close_all(void)
+{
+ struct close_me *c;
+ for (c = close_me_head; c; c = c->next) {
+ close(c->fd);
+ }
+ close_me_head = NULL;
+}
+
+/* squirrel != NULL means we squirrel away copies of stdin, stdout,
+ * and stderr if they are redirected. */
+static int setup_redirects(struct child_prog *prog, int squirrel[])
+{
+ int openfd, mode;
+ struct redir_struct *redir;
+
+ for (redir = prog->redirects; redir; redir = redir->next) {
+ if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
+ /* something went wrong in the parse. Pretend it didn't happen */
+ continue;
+ }
+ if (redir->dup == -1) {
+ mode = redir_table[redir->type].mode;
+ openfd = open(redir->word.gl_pathv[0], mode, 0666);
+ if (openfd < 0) {
+ /* this could get lost if stderr has been redirected, but
+ bash and ash both lose it as well (though zsh doesn't!) */
+ bb_perror_msg("error opening %s", redir->word.gl_pathv[0]);
+ return 1;
+ }
+ } else {
+ openfd = redir->dup;
+ }
+
+ if (openfd != redir->fd) {
+ if (squirrel && redir->fd < 3) {
+ squirrel[redir->fd] = dup(redir->fd);
+ }
+ if (openfd == -3) {
+ close(openfd);
+ } else {
+ dup2(openfd, redir->fd);
+ if (redir->dup == -1)
+ close (openfd);
+ }
+ }
+ }
+ return 0;
+}
+
+static void restore_redirects(int squirrel[])
+{
+ int i, fd;
+ for (i = 0; i < 3; i++) {
+ fd = squirrel[i];
+ if (fd != -1) {
+ /* No error checking. I sure wouldn't know what
+ * to do with an error if I found one! */
+ dup2(fd, i);
+ close(fd);
+ }
+ }
+}
+
+/* never returns */
+/* XXX no exit() here. If you don't exec, use _exit instead.
+ * The at_exit handlers apparently confuse the calling process,
+ * in particular stdin handling. Not sure why? */
+static void pseudo_exec(struct child_prog *child)
+{
+ int i, rcode;
+ char *p;
+ const struct built_in_command *x;
+ if (child->argv) {
+ for (i = 0; is_assignment(child->argv[i]); i++) {
+ debug_printf("pid %d environment modification: %s\n",
+ getpid(), child->argv[i]);
+ p = insert_var_value(child->argv[i]);
+ putenv(strdup(p));
+ if (p != child->argv[i])
+ free(p);
+ }
+ child->argv += i; /* XXX this hack isn't so horrible, since we are about
+ to exit, and therefore don't need to keep data
+ structures consistent for free() use. */
+ /* If a variable is assigned in a forest, and nobody listens,
+ * was it ever really set?
+ */
+ if (child->argv[0] == NULL) {
+ _exit(EXIT_SUCCESS);
+ }
+
+ /*
+ * Check if the command matches any of the builtins.
+ * Depending on context, this might be redundant. But it's
+ * easier to waste a few CPU cycles than it is to figure out
+ * if this is one of those cases.
+ */
+ for (x = bltins; x->cmd; x++) {
+ if (strcmp(child->argv[0], x->cmd) == 0 ) {
+ debug_printf("builtin exec %s\n", child->argv[0]);
+ rcode = x->function(child);
+ fflush(stdout);
+ _exit(rcode);
+ }
+ }
+
+ /* Check if the command matches any busybox internal commands
+ * ("applets") here.
+ * FIXME: This feature is not 100% safe, since
+ * BusyBox is not fully reentrant, so we have no guarantee the things
+ * from the .bss are still zeroed, or that things from .data are still
+ * at their defaults. We could exec ourself from /proc/self/exe, but I
+ * really dislike relying on /proc for things. We could exec ourself
+ * from global_argv[0], but if we are in a chroot, we may not be able
+ * to find ourself... */
+#if ENABLE_FEATURE_SH_STANDALONE_SHELL
+ {
+ int argc_l;
+ char** argv_l = child->argv;
+ char *name = child->argv[0];
+
+ /* Count argc for use in a second... */
+ for (argc_l = 0; *argv_l; argv_l++, argc_l++)
+ /**/;
+ optind = 1;
+ debug_printf("running applet %s\n", name);
+ run_applet_by_name(name, argc_l, child->argv);
+ }
+#endif
+ debug_printf("exec of %s\n", child->argv[0]);
+ execvp(child->argv[0], child->argv);
+ bb_perror_msg("cannot exec: %s", child->argv[0]);
+ _exit(1);
+ } else if (child->group) {
+ debug_printf("runtime nesting to group\n");
+ interactive = 0; /* crucial!!!! */
+ rcode = run_list_real(child->group);
+ /* OK to leak memory by not calling free_pipe_list,
+ * since this process is about to exit */
+ _exit(rcode);
+ } else {
+ /* Can happen. See what bash does with ">foo" by itself. */
+ debug_printf("trying to pseudo_exec null command\n");
+ _exit(EXIT_SUCCESS);
+ }
+}
+
+static void insert_bg_job(struct pipe *pi)
+{
+ struct pipe *thejob;
+
+ /* Linear search for the ID of the job to use */
+ pi->jobid = 1;
+ for (thejob = job_list; thejob; thejob = thejob->next)
+ if (thejob->jobid >= pi->jobid)
+ pi->jobid = thejob->jobid + 1;
+
+ /* add thejob to the list of running jobs */
+ if (!job_list) {
+ thejob = job_list = xmalloc(sizeof(*thejob));
+ } else {
+ for (thejob = job_list; thejob->next; thejob = thejob->next)
+ /* nothing */;
+ thejob->next = xmalloc(sizeof(*thejob));
+ thejob = thejob->next;
+ }
+
+ /* physically copy the struct job */
+ memcpy(thejob, pi, sizeof(struct pipe));
+ thejob->next = NULL;
+ thejob->running_progs = thejob->num_progs;
+ thejob->stopped_progs = 0;
+ thejob->text = xmalloc(BUFSIZ); /* cmdedit buffer size */
+
+ //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0])
+ {
+ char *bar = thejob->text;
+ char **foo = pi->progs[0].argv;
+ if (foo)
+ while (*foo)
+ bar += sprintf(bar, "%s ", *foo++);
+ }
+
+ /* we don't wait for background thejobs to return -- append it
+ to the list of backgrounded thejobs and leave it alone */
+ printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid);
+ last_bg_pid = thejob->progs[0].pid;
+ last_jobid = thejob->jobid;
+}
+
+/* remove a backgrounded job */
+static void remove_bg_job(struct pipe *pi)
+{
+ struct pipe *prev_pipe;
+
+ if (pi == job_list) {
+ job_list = pi->next;
+ } else {
+ prev_pipe = job_list;
+ while (prev_pipe->next != pi)
+ prev_pipe = prev_pipe->next;
+ prev_pipe->next = pi->next;
+ }
+ if (job_list)
+ last_jobid = job_list->jobid;
+ else
+ last_jobid = 0;
+
+ pi->stopped_progs = 0;
+ free_pipe(pi, 0);
+ free(pi);
+}
+
+/* Checks to see if any processes have exited -- if they
+ have, figure out why and see if a job has completed */
+static int checkjobs(struct pipe* fg_pipe)
+{
+ int attributes;
+ int status;
+ int prognum = 0;
+ struct pipe *pi;
+ pid_t childpid;
+
+ attributes = WUNTRACED;
+ if (fg_pipe == NULL) {
+ attributes |= WNOHANG;
+ }
+
+ while ((childpid = waitpid(-1, &status, attributes)) > 0) {
+ if (fg_pipe) {
+ int i, rcode = 0;
+ for (i = 0; i < fg_pipe->num_progs; i++) {
+ if (fg_pipe->progs[i].pid == childpid) {
+ if (i == fg_pipe->num_progs-1)
+ rcode = WEXITSTATUS(status);
+ fg_pipe->num_progs--;
+ return rcode;
+ }
+ }
+ }
+
+ for (pi = job_list; pi; pi = pi->next) {
+ prognum = 0;
+ while (prognum < pi->num_progs && pi->progs[prognum].pid != childpid) {
+ prognum++;
+ }
+ if (prognum < pi->num_progs)
+ break;
+ }
+
+ if (pi == NULL) {
+ debug_printf("checkjobs: pid %d was not in our list!\n",
+ childpid);
+ continue;
+ }
+
+ if (WIFEXITED(status) || WIFSIGNALED(status)) {
+ /* child exited */
+ pi->running_progs--;
+ pi->progs[prognum].pid = 0;
+
+ if (!pi->running_progs) {
+ printf(JOB_STATUS_FORMAT, pi->jobid,
+ "Done", pi->text);
+ remove_bg_job(pi);
+ }
+ } else {
+ /* child stopped */
+ pi->stopped_progs++;
+ pi->progs[prognum].is_stopped = 1;
+ }
+ }
+
+ if (childpid == -1 && errno != ECHILD)
+ bb_perror_msg("waitpid");
+
+ /* move the shell to the foreground */
+ //if (interactive && tcsetpgrp(shell_terminal, getpgid(0)))
+ // bb_perror_msg("tcsetpgrp-2");
+ return -1;
+}
+
+/* run_pipe_real() starts all the jobs, but doesn't wait for anything
+ * to finish. See checkjobs().
+ *
+ * return code is normally -1, when the caller has to wait for children
+ * to finish to determine the exit status of the pipe. If the pipe
+ * is a simple builtin command, however, the action is done by the
+ * time run_pipe_real returns, and the exit code is provided as the
+ * return value.
+ *
+ * The input of the pipe is always stdin, the output is always
+ * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
+ * because it tries to avoid running the command substitution in
+ * subshell, when that is in fact necessary. The subshell process
+ * now has its stdout directed to the input of the appropriate pipe,
+ * so this routine is noticeably simpler.
+ */
+static int run_pipe_real(struct pipe *pi)
+{
+ int i;
+ int nextin, nextout;
+ int pipefds[2]; /* pipefds[0] is for reading */
+ struct child_prog *child;
+ const struct built_in_command *x;
+ char *p;
+
+ nextin = 0;
+ pi->pgrp = -1;
+
+ /* Check if this is a simple builtin (not part of a pipe).
+ * Builtins within pipes have to fork anyway, and are handled in
+ * pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
+ */
+ child = &(pi->progs[0]);
+ if (pi->num_progs == 1 && child->group && child->subshell == 0) {
+ int squirrel[] = { -1, -1, -1 };
+ int rcode;
+ debug_printf("non-subshell grouping\n");
+ setup_redirects(child, squirrel);
+ /* XXX could we merge code with following builtin case,
+ * by creating a pseudo builtin that calls run_list_real? */
+ rcode = run_list_real(child->group);
+ restore_redirects(squirrel);
+ return rcode;
+ } else if (pi->num_progs == 1 && pi->progs[0].argv != NULL) {
+ for (i = 0; is_assignment(child->argv[i]); i++)
+ /* nothing */;
+ if (i != 0 && child->argv[i] == NULL) {
+ /* assignments, but no command: set the local environment */
+ for (i = 0; child->argv[i] != NULL; i++) {
+ /* Ok, this case is tricky. We have to decide if this is a
+ * local variable, or an already exported variable. If it is
+ * already exported, we have to export the new value. If it is
+ * not exported, we need only set this as a local variable.
+ * This junk is all to decide whether or not to export this
+ * variable. */
+ int export_me = 0;
+ char *name, *value;
+ name = xstrdup(child->argv[i]);
+ debug_printf("Local environment set: %s\n", name);
+ value = strchr(name, '=');
+ if (value)
+ *value = 0;
+ if (get_local_var(name)) {
+ export_me = 1;
+ }
+ free(name);
+ p = insert_var_value(child->argv[i]);
+ set_local_var(p, export_me);
+ if (p != child->argv[i])
+ free(p);
+ }
+ return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
+ }
+ for (i = 0; is_assignment(child->argv[i]); i++) {
+ p = insert_var_value(child->argv[i]);
+ putenv(strdup(p));
+ if (p != child->argv[i]) {
+ child->sp--;
+ free(p);
+ }
+ }
+ if (child->sp) {
+ char *str = NULL;
+
+ str = make_string((child->argv + i));
+ parse_string_outer(str, FLAG_EXIT_FROM_LOOP | FLAG_REPARSING);
+ free(str);
+ return last_return_code;
+ }
+ for (x = bltins; x->cmd; x++) {
+ if (strcmp(child->argv[i], x->cmd) == 0 ) {
+ int squirrel[] = { -1, -1, -1 };
+ int rcode;
+ if (x->function == builtin_exec && child->argv[i+1] == NULL) {
+ debug_printf("magic exec\n");
+ setup_redirects(child,NULL);
+ return EXIT_SUCCESS;
+ }
+ debug_printf("builtin inline %s\n", child->argv[0]);
+ /* XXX setup_redirects acts on file descriptors, not FILEs.
+ * This is perfect for work that comes after exec().
+ * Is it really safe for inline use? Experimentally,
+ * things seem to work with glibc. */
+ setup_redirects(child, squirrel);
+ child->argv += i; /* XXX horrible hack */
+ rcode = x->function(child);
+ child->argv -= i; /* XXX restore hack so free() can work right */
+ restore_redirects(squirrel);
+ return rcode;
+ }
+ }
+ }
+
+ for (i = 0; i < pi->num_progs; i++) {
+ child = &(pi->progs[i]);
+
+ /* pipes are inserted between pairs of commands */
+ if ((i + 1) < pi->num_progs) {
+ if (pipe(pipefds) < 0)
+ bb_perror_msg_and_die("pipe");
+ nextout = pipefds[1];
+ } else {
+ nextout = 1;
+ pipefds[0] = -1;
+ }
+
+ /* XXX test for failed fork()? */
+#if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
+ child->pid = fork();
+#else
+ child->pid = vfork();
+#endif
+ if (!child->pid) {
+ /* Set the handling for job control signals back to the default. */
+ signal(SIGINT, SIG_DFL);
+ signal(SIGQUIT, SIG_DFL);
+ signal(SIGTERM, SIG_DFL);
+ signal(SIGTSTP, SIG_DFL);
+ signal(SIGTTIN, SIG_DFL);
+ signal(SIGTTOU, SIG_DFL);
+ signal(SIGCHLD, SIG_DFL);
+
+ close_all();
+
+ if (nextin != 0) {
+ dup2(nextin, 0);
+ close(nextin);
+ }
+ if (nextout != 1) {
+ dup2(nextout, 1);
+ close(nextout);
+ }
+ if (pipefds[0] != -1) {
+ close(pipefds[0]); /* opposite end of our output pipe */
+ }
+
+ /* Like bash, explicit redirects override pipes,
+ * and the pipe fd is available for dup'ing. */
+ setup_redirects(child,NULL);
+
+ if (interactive && pi->followup != PIPE_BG) {
+ /* If we (the child) win the race, put ourselves in the process
+ * group whose leader is the first process in this pipe. */
+ if (pi->pgrp < 0) {
+ pi->pgrp = getpid();
+ }
+ if (setpgid(0, pi->pgrp) == 0) {
+ tcsetpgrp(2, pi->pgrp);
+ }
+ }
+
+ pseudo_exec(child);
+ }
+
+ /* put our child in the process group whose leader is the
+ first process in this pipe */
+ if (pi->pgrp < 0) {
+ pi->pgrp = child->pid;
+ }
+ /* Don't check for errors. The child may be dead already,
+ * in which case setpgid returns error code EACCES. */
+ setpgid(child->pid, pi->pgrp);
+
+ if (nextin != 0)
+ close(nextin);
+ if (nextout != 1)
+ close(nextout);
+
+ /* If there isn't another process, nextin is garbage
+ but it doesn't matter */
+ nextin = pipefds[0];
+ }
+ return -1;
+}
+
+static int run_list_real(struct pipe *pi)
+{
+ char *save_name = NULL;
+ char **list = NULL;
+ char **save_list = NULL;
+ struct pipe *rpipe;
+ int flag_rep = 0;
+ int save_num_progs;
+ int rcode = 0, flag_skip = 1;
+ int flag_restore = 0;
+ int if_code = 0, next_if_code = 0; /* need double-buffer to handle elif */
+ reserved_style rmode, skip_more_in_this_rmode = RES_XXXX;
+ /* check syntax for "for" */
+ for (rpipe = pi; rpipe; rpipe = rpipe->next) {
+ if ((rpipe->r_mode == RES_IN || rpipe->r_mode == RES_FOR)
+ && (rpipe->next == NULL)
+ ) {
+ syntax();
+ return 1;
+ }
+ if ((rpipe->r_mode == RES_IN && rpipe->next->r_mode == RES_IN && rpipe->next->progs->argv != NULL)
+ || (rpipe->r_mode == RES_FOR && rpipe->next->r_mode != RES_IN)
+ ) {
+ syntax();
+ return 1;
+ }
+ }
+ for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
+ if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL
+ || pi->r_mode == RES_FOR
+ ) {
+ flag_restore = 0;
+ if (!rpipe) {
+ flag_rep = 0;
+ rpipe = pi;
+ }
+ }
+ rmode = pi->r_mode;
+ debug_printf("rmode=%d if_code=%d next_if_code=%d skip_more=%d\n",
+ rmode, if_code, next_if_code, skip_more_in_this_rmode);
+ if (rmode == skip_more_in_this_rmode && flag_skip) {
+ if (pi->followup == PIPE_SEQ)
+ flag_skip = 0;
+ continue;
+ }
+ flag_skip = 1;
+ skip_more_in_this_rmode = RES_XXXX;
+ if (rmode == RES_THEN || rmode == RES_ELSE)
+ if_code = next_if_code;
+ if (rmode == RES_THEN && if_code)
+ continue;
+ if (rmode == RES_ELSE && !if_code)
+ continue;
+ if (rmode == RES_ELIF && !if_code)
+ break;
+ if (rmode == RES_FOR && pi->num_progs) {
+ if (!list) {
+ /* if no variable values after "in" we skip "for" */
+ if (!pi->next->progs->argv)
+ continue;
+ /* create list of variable values */
+ list = make_list_in(pi->next->progs->argv,
+ pi->progs->argv[0]);
+ save_list = list;
+ save_name = pi->progs->argv[0];
+ pi->progs->argv[0] = NULL;
+ flag_rep = 1;
+ }
+ if (!*list) {
+ free(pi->progs->argv[0]);
+ free(save_list);
+ list = NULL;
+ flag_rep = 0;
+ pi->progs->argv[0] = save_name;
+ pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
+ continue;
+ } else {
+ /* insert new value from list for variable */
+ if (pi->progs->argv[0])
+ free(pi->progs->argv[0]);
+ pi->progs->argv[0] = *list++;
+ pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
+ }
+ }
+ if (rmode == RES_IN)
+ continue;
+ if (rmode == RES_DO) {
+ if (!flag_rep)
+ continue;
+ }
+ if ((rmode == RES_DONE)) {
+ if (flag_rep) {
+ flag_restore = 1;
+ } else {
+ rpipe = NULL;
+ }
+ }
+ if (pi->num_progs == 0)
+ continue;
+ save_num_progs = pi->num_progs; /* save number of programs */
+ rcode = run_pipe_real(pi);
+ debug_printf("run_pipe_real returned %d\n",rcode);
+ if (rcode != -1) {
+ /* We only ran a builtin: rcode was set by the return value
+ * of run_pipe_real(), and we don't need to wait for anything. */
+ } else if (pi->followup == PIPE_BG) {
+ /* XXX check bash's behavior with nontrivial pipes */
+ /* XXX compute jobid */
+ /* XXX what does bash do with attempts to background builtins? */
+ insert_bg_job(pi);
+ rcode = EXIT_SUCCESS;
+ } else {
+ if (interactive) {
+ /* move the new process group into the foreground */
+ if (tcsetpgrp(shell_terminal, pi->pgrp) && errno != ENOTTY)
+ bb_perror_msg("tcsetpgrp-3");
+ rcode = checkjobs(pi);
+ /* move the shell to the foreground */
+ if (tcsetpgrp(shell_terminal, getpgid(0)) && errno != ENOTTY)
+ bb_perror_msg("tcsetpgrp-4");
+ } else {
+ rcode = checkjobs(pi);
+ }
+ debug_printf("checkjobs returned %d\n",rcode);
+ }
+ last_return_code = rcode;
+ pi->num_progs = save_num_progs; /* restore number of programs */
+ if ( rmode == RES_IF || rmode == RES_ELIF )
+ next_if_code = rcode; /* can be overwritten a number of times */
+ if (rmode == RES_WHILE)
+ flag_rep = !last_return_code;
+ if (rmode == RES_UNTIL)
+ flag_rep = last_return_code;
+ if ((rcode == EXIT_SUCCESS && pi->followup == PIPE_OR)
+ || (rcode != EXIT_SUCCESS && pi->followup == PIPE_AND)
+ ) {
+ skip_more_in_this_rmode = rmode;
+ }
+ checkjobs(NULL);
+ }
+ return rcode;
+}
+
+/* return code is the exit status of the pipe */
+static int free_pipe(struct pipe *pi, int indent)
+{
+ char **p;
+ struct child_prog *child;
+ struct redir_struct *r, *rnext;
+ int a, i, ret_code = 0;
+
+ if (pi->stopped_progs > 0)
+ return ret_code;
+ final_printf("%s run pipe: (pid %d)\n", indenter(indent), getpid());
+ for (i = 0; i < pi->num_progs; i++) {
+ child = &pi->progs[i];
+ final_printf("%s command %d:\n", indenter(indent), i);
+ if (child->argv) {
+ for (a = 0, p = child->argv; *p; a++, p++) {
+ final_printf("%s argv[%d] = %s\n", indenter(indent), a, *p);
+ }
+ globfree(&child->glob_result);
+ child->argv = NULL;
+ } else if (child->group) {
+ final_printf("%s begin group (subshell:%d)\n", indenter(indent), child->subshell);
+ ret_code = free_pipe_list(child->group, indent+3);
+ final_printf("%s end group\n", indenter(indent));
+ } else {
+ final_printf("%s (nil)\n", indenter(indent));
+ }
+ for (r = child->redirects; r; r = rnext) {
+ final_printf("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->type].descrip);
+ if (r->dup == -1) {
+ /* guard against the case >$FOO, where foo is unset or blank */
+ if (r->word.gl_pathv) {
+ final_printf(" %s\n", *r->word.gl_pathv);
+ globfree(&r->word);
+ }
+ } else {
+ final_printf("&%d\n", r->dup);
+ }
+ rnext = r->next;
+ free(r);
+ }
+ child->redirects = NULL;
+ }
+ free(pi->progs); /* children are an array, they get freed all at once */
+ pi->progs = NULL;
+ return ret_code;
+}
+
+static int free_pipe_list(struct pipe *head, int indent)
+{
+ int rcode = 0; /* if list has no members */
+ struct pipe *pi, *next;
+ for (pi = head; pi; pi = next) {
+ final_printf("%s pipe reserved mode %d\n", indenter(indent), pi->r_mode);
+ rcode = free_pipe(pi, indent);
+ final_printf("%s pipe followup code %d\n", indenter(indent), pi->followup);
+ next = pi->next;
+ pi->next = NULL;
+ free(pi);
+ }
+ return rcode;
+}
+
+/* Select which version we will use */
+static int run_list(struct pipe *pi)
+{
+ int rcode = 0;
+ if (fake_mode == 0) {
+ rcode = run_list_real(pi);
+ }
+ /* free_pipe_list has the side effect of clearing memory
+ * In the long run that function can be merged with run_list_real,
+ * but doing that now would hobble the debugging effort. */
+ free_pipe_list(pi,0);
+ return rcode;
+}
+
+/* The API for glob is arguably broken. This routine pushes a non-matching
+ * string into the output structure, removing non-backslashed backslashes.
+ * If someone can prove me wrong, by performing this function within the
+ * original glob(3) api, feel free to rewrite this routine into oblivion.
+ * Return code (0 vs. GLOB_NOSPACE) matches glob(3).
+ * XXX broken if the last character is '\\', check that before calling.
+ */
+static int globhack(const char *src, int flags, glob_t *pglob)
+{
+ int cnt = 0, pathc;
+ const char *s;
+ char *dest;
+ for (cnt = 1, s = src; s && *s; s++) {
+ if (*s == '\\') s++;
+ cnt++;
+ }
+ dest = malloc(cnt);
+ if (!dest) return GLOB_NOSPACE;
+ if (!(flags & GLOB_APPEND)) {
+ pglob->gl_pathv = NULL;
+ pglob->gl_pathc = 0;
+ pglob->gl_offs = 0;
+ pglob->gl_offs = 0;
+ }
+ pathc = ++pglob->gl_pathc;
+ pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv));
+ if (pglob->gl_pathv == NULL) return GLOB_NOSPACE;
+ pglob->gl_pathv[pathc-1] = dest;
+ pglob->gl_pathv[pathc] = NULL;
+ for (s = src; s && *s; s++, dest++) {
+ if (*s == '\\') s++;
+ *dest = *s;
+ }
+ *dest = '\0';
+ return 0;
+}
+
+/* XXX broken if the last character is '\\', check that before calling */
+static int glob_needed(const char *s)
+{
+ for (; *s; s++) {
+ if (*s == '\\') s++;
+ if (strchr("*[?", *s)) return 1;
+ }
+ return 0;
+}
+
+static int xglob(o_string *dest, int flags, glob_t *pglob)
+{
+ int gr;
+
+ /* short-circuit for null word */
+ /* we can code this better when the debug_printf's are gone */
+ if (dest->length == 0) {
+ if (dest->nonnull) {
+ /* bash man page calls this an "explicit" null */
+ gr = globhack(dest->data, flags, pglob);
+ debug_printf("globhack returned %d\n", gr);
+ } else {
+ return 0;
+ }
+ } else if (glob_needed(dest->data)) {
+ gr = glob(dest->data, flags, NULL, pglob);
+ debug_printf("glob returned %d\n", gr);
+ if (gr == GLOB_NOMATCH) {
+ /* quote removal, or more accurately, backslash removal */
+ gr = globhack(dest->data, flags, pglob);
+ debug_printf("globhack returned %d\n", gr);
+ }
+ } else {
+ gr = globhack(dest->data, flags, pglob);
+ debug_printf("globhack returned %d\n", gr);
+ }
+ if (gr == GLOB_NOSPACE)
+ bb_error_msg_and_die("out of memory during glob");
+ if (gr != 0) { /* GLOB_ABORTED ? */
+ bb_error_msg("glob(3) error %d", gr);
+ }
+ /* globprint(glob_target); */
+ return gr;
+}
+
+/* This is used to get/check local shell variables */
+static const char *get_local_var(const char *s)
+{
+ struct variables *cur;
+
+ if (!s)
+ return NULL;
+ for (cur = top_vars; cur; cur = cur->next)
+ if (strcmp(cur->name, s) == 0)
+ return cur->value;
+ return NULL;
+}
+
+/* This is used to set local shell variables
+ flg_export == 0 if only local (not exporting) variable
+ flg_export == 1 if "new" exporting environ
+ flg_export > 1 if current startup environ (not call putenv()) */
+static int set_local_var(const char *s, int flg_export)
+{
+ char *name, *value;
+ int result = 0;
+ struct variables *cur;
+
+ name = strdup(s);
+
+ /* Assume when we enter this function that we are already in
+ * NAME=VALUE format. So the first order of business is to
+ * split 's' on the '=' into 'name' and 'value' */
+ value = strchr(name, '=');
+ if (value == 0 && ++value == 0) {
+ free(name);
+ return -1;
+ }
+ *value++ = 0;
+
+ for (cur = top_vars; cur; cur = cur->next) {
+ if (strcmp(cur->name, name) == 0)
+ break;
+ }
+
+ if (cur) {
+ if (strcmp(cur->value, value) == 0) {
+ if (flg_export > 0 && cur->flg_export == 0)
+ cur->flg_export = flg_export;
+ else
+ result++;
+ } else {
+ if (cur->flg_read_only) {
+ bb_error_msg("%s: readonly variable", name);
+ result = -1;
+ } else {
+ if (flg_export > 0 || cur->flg_export > 1)
+ cur->flg_export = 1;
+ free((char*)cur->value);
+
+ cur->value = strdup(value);
+ }
+ }
+ } else {
+ cur = malloc(sizeof(struct variables));
+ if (!cur) {
+ result = -1;
+ } else {
+ cur->name = strdup(name);
+ if (cur->name) {
+ free(cur);
+ result = -1;
+ } else {
+ struct variables *bottom = top_vars;
+ cur->value = strdup(value);
+ cur->next = 0;
+ cur->flg_export = flg_export;
+ cur->flg_read_only = 0;
+ while (bottom->next)
+ bottom = bottom->next;
+ bottom->next = cur;
+ }
+ }
+ }
+
+ if (result == 0 && cur->flg_export == 1) {
+ *(value-1) = '=';
+ result = putenv(name);
+ } else {
+ free(name);
+ if (result > 0) /* equivalent to previous set */
+ result = 0;
+ }
+ return result;
+}
+
+static void unset_local_var(const char *name)
+{
+ struct variables *cur;
+
+ if (name) {
+ for (cur = top_vars; cur; cur = cur->next) {
+ if (strcmp(cur->name, name) == 0)
+ break;
+ }
+ if (cur != 0) {
+ struct variables *next = top_vars;
+ if (cur->flg_read_only) {
+ bb_error_msg("%s: readonly variable", name);
+ return;
+ }
+ if (cur->flg_export)
+ unsetenv(cur->name);
+ free((char*)cur->name);
+ free((char*)cur->value);
+ while (next->next != cur)
+ next = next->next;
+ next->next = cur->next;
+ free(cur);
+ }
+ }
+}
+
+static int is_assignment(const char *s)
+{
+ if (!s || !isalpha(*s))
+ return 0;
+ s++;
+ while (isalnum(*s) || *s == '_')
+ s++;
+ return *s == '=';
+}
+
+/* the src parameter allows us to peek forward to a possible &n syntax
+ * for file descriptor duplication, e.g., "2>&1".
+ * Return code is 0 normally, 1 if a syntax error is detected in src.
+ * Resource errors (in xmalloc) cause the process to exit */
+static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
+ struct in_str *input)
+{
+ struct child_prog *child = ctx->child;
+ struct redir_struct *redir = child->redirects;
+ struct redir_struct *last_redir = NULL;
+
+ /* Create a new redir_struct and drop it onto the end of the linked list */
+ while (redir) {
+ last_redir = redir;
+ redir = redir->next;
+ }
+ redir = xmalloc(sizeof(struct redir_struct));
+ redir->next = NULL;
+ redir->word.gl_pathv = NULL;
+ if (last_redir) {
+ last_redir->next = redir;
+ } else {
+ child->redirects = redir;
+ }
+
+ redir->type = style;
+ redir->fd = (fd == -1) ? redir_table[style].default_fd : fd;
+
+ debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
+
+ /* Check for a '2>&1' type redirect */
+ redir->dup = redirect_dup_num(input);
+ if (redir->dup == -2) return 1; /* syntax error */
+ if (redir->dup != -1) {
+ /* Erik had a check here that the file descriptor in question
+ * is legit; I postpone that to "run time"
+ * A "-" representation of "close me" shows up as a -3 here */
+ debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
+ } else {
+ /* We do _not_ try to open the file that src points to,
+ * since we need to return and let src be expanded first.
+ * Set ctx->pending_redirect, so we know what to do at the
+ * end of the next parsed word.
+ */
+ ctx->pending_redirect = redir;
+ }
+ return 0;
+}
+
+static struct pipe *new_pipe(void) {
+ struct pipe *pi;
+ pi = xmalloc(sizeof(struct pipe));
+ pi->num_progs = 0;
+ pi->progs = NULL;
+ pi->next = NULL;
+ pi->followup = 0; /* invalid */
+ pi->r_mode = RES_NONE;
+ return pi;
+}
+
+static void initialize_context(struct p_context *ctx)
+{
+ ctx->pipe = NULL;
+ ctx->pending_redirect = NULL;
+ ctx->child = NULL;
+ ctx->list_head = new_pipe();
+ ctx->pipe = ctx->list_head;
+ ctx->w = RES_NONE;
+ ctx->stack = NULL;
+ ctx->old_flag = 0;
+ done_command(ctx); /* creates the memory for working child */
+}
+
+/* normal return is 0
+ * if a reserved word is found, and processed, return 1
+ * should handle if, then, elif, else, fi, for, while, until, do, done.
+ * case, function, and select are obnoxious, save those for later.
+ */
+static int reserved_word(o_string *dest, struct p_context *ctx)
+{
+ struct reserved_combo {
+ const char *literal;
+ int code;
+ long flag;
+ };
+ /* Mostly a list of accepted follow-up reserved words.
+ * FLAG_END means we are done with the sequence, and are ready
+ * to turn the compound list into a command.
+ * FLAG_START means the word must start a new compound list.
+ */
+ static const struct reserved_combo reserved_list[] = {
+ { "if", RES_IF, FLAG_THEN | FLAG_START },
+ { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
+ { "elif", RES_ELIF, FLAG_THEN },
+ { "else", RES_ELSE, FLAG_FI },
+ { "fi", RES_FI, FLAG_END },
+ { "for", RES_FOR, FLAG_IN | FLAG_START },
+ { "while", RES_WHILE, FLAG_DO | FLAG_START },
+ { "until", RES_UNTIL, FLAG_DO | FLAG_START },
+ { "in", RES_IN, FLAG_DO },
+ { "do", RES_DO, FLAG_DONE },
+ { "done", RES_DONE, FLAG_END }
+ };
+ const struct reserved_combo *r;
+#define NRES sizeof(reserved_list)/sizeof(reserved_list[0])
+
+ for (r = reserved_list; r < reserved_list+NRES; r++) {
+ if (strcmp(dest->data, r->literal) == 0) {
+ debug_printf("found reserved word %s, code %d\n",r->literal,r->code);
+ if (r->flag & FLAG_START) {
+ struct p_context *new = xmalloc(sizeof(struct p_context));
+ debug_printf("push stack\n");
+ if (ctx->w == RES_IN || ctx->w == RES_FOR) {
+ syntax();
+ free(new);
+ ctx->w = RES_SNTX;
+ b_reset(dest);
+ return 1;
+ }
+ *new = *ctx; /* physical copy */
+ initialize_context(ctx);
+ ctx->stack = new;
+ } else if (ctx->w == RES_NONE || !(ctx->old_flag & (1 << r->code))) {
+ syntax();
+ ctx->w = RES_SNTX;
+ b_reset(dest);
+ return 1;
+ }
+ ctx->w = r->code;
+ ctx->old_flag = r->flag;
+ if (ctx->old_flag & FLAG_END) {
+ struct p_context *old;
+ debug_printf("pop stack\n");
+ done_pipe(ctx,PIPE_SEQ);
+ old = ctx->stack;
+ old->child->group = ctx->list_head;
+ old->child->subshell = 0;
+ *ctx = *old; /* physical copy */
+ free(old);
+ }
+ b_reset (dest);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/* normal return is 0.
+ * Syntax or xglob errors return 1. */
+static int done_word(o_string *dest, struct p_context *ctx)
+{
+ struct child_prog *child = ctx->child;
+ glob_t *glob_target;
+ int gr, flags = 0;
+
+ debug_printf("done_word: %s %p\n", dest->data, child);
+ if (dest->length == 0 && !dest->nonnull) {
+ debug_printf(" true null, ignored\n");
+ return 0;
+ }
+ if (ctx->pending_redirect) {
+ glob_target = &ctx->pending_redirect->word;
+ } else {
+ if (child->group) {
+ syntax();
+ return 1; /* syntax error, groups and arglists don't mix */
+ }
+ if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
+ debug_printf("checking %s for reserved-ness\n",dest->data);
+ if (reserved_word(dest,ctx))
+ return (ctx->w == RES_SNTX);
+ }
+ glob_target = &child->glob_result;
+ if (child->argv) flags |= GLOB_APPEND;
+ }
+ gr = xglob(dest, flags, glob_target);
+ if (gr != 0) return 1;
+
+ b_reset(dest);
+ if (ctx->pending_redirect) {
+ ctx->pending_redirect = NULL;
+ if (glob_target->gl_pathc != 1) {
+ bb_error_msg("ambiguous redirect");
+ return 1;
+ }
+ } else {
+ child->argv = glob_target->gl_pathv;
+ }
+ if (ctx->w == RES_FOR) {
+ done_word(dest,ctx);
+ done_pipe(ctx,PIPE_SEQ);
+ }
+ return 0;
+}
+
+/* The only possible error here is out of memory, in which case
+ * xmalloc exits. */
+static int done_command(struct p_context *ctx)
+{
+ /* The child is really already in the pipe structure, so
+ * advance the pipe counter and make a new, null child.
+ * Only real trickiness here is that the uncommitted
+ * child structure, to which ctx->child points, is not
+ * counted in pi->num_progs. */
+ struct pipe *pi = ctx->pipe;
+ struct child_prog *prog = ctx->child;
+
+ if (prog && prog->group == NULL
+ && prog->argv == NULL
+ && prog->redirects == NULL) {
+ debug_printf("done_command: skipping null command\n");
+ return 0;
+ } else if (prog) {
+ pi->num_progs++;
+ debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs);
+ } else {
+ debug_printf("done_command: initializing\n");
+ }
+ pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
+
+ prog = pi->progs + pi->num_progs;
+ prog->redirects = NULL;
+ prog->argv = NULL;
+ prog->is_stopped = 0;
+ prog->group = NULL;
+ prog->glob_result.gl_pathv = NULL;
+ prog->family = pi;
+ prog->sp = 0;
+ ctx->child = prog;
+ prog->type = ctx->type;
+
+ /* but ctx->pipe and ctx->list_head remain unchanged */
+ return 0;
+}
+
+static int done_pipe(struct p_context *ctx, pipe_style type)
+{
+ struct pipe *new_p;
+ done_command(ctx); /* implicit closure of previous command */
+ debug_printf("done_pipe, type %d\n", type);
+ ctx->pipe->followup = type;
+ ctx->pipe->r_mode = ctx->w;
+ new_p = new_pipe();
+ ctx->pipe->next = new_p;
+ ctx->pipe = new_p;
+ ctx->child = NULL;
+ done_command(ctx); /* set up new pipe to accept commands */
+ return 0;
+}
+
+/* peek ahead in the in_str to find out if we have a "&n" construct,
+ * as in "2>&1", that represents duplicating a file descriptor.
+ * returns either -2 (syntax error), -1 (no &), or the number found.
+ */
+static int redirect_dup_num(struct in_str *input)
+{
+ int ch, d = 0, ok = 0;
+ ch = b_peek(input);
+ if (ch != '&') return -1;
+
+ b_getch(input); /* get the & */
+ ch = b_peek(input);
+ if (ch == '-') {
+ b_getch(input);
+ return -3; /* "-" represents "close me" */
+ }
+ while (isdigit(ch)) {
+ d = d*10+(ch-'0');
+ ok = 1;
+ b_getch(input);
+ ch = b_peek(input);
+ }
+ if (ok) return d;
+
+ bb_error_msg("ambiguous redirect");
+ return -2;
+}
+
+/* If a redirect is immediately preceded by a number, that number is
+ * supposed to tell which file descriptor to redirect. This routine
+ * looks for such preceding numbers. In an ideal world this routine
+ * needs to handle all the following classes of redirects...
+ * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
+ * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
+ * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
+ * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
+ * A -1 output from this program means no valid number was found, so the
+ * caller should use the appropriate default for this redirection.
+ */
+static int redirect_opt_num(o_string *o)
+{
+ int num;
+
+ if (o->length == 0)
+ return -1;
+ for (num = 0; num < o->length; num++) {
+ if (!isdigit(*(o->data + num))) {
+ return -1;
+ }
+ }
+ /* reuse num (and save an int) */
+ num = atoi(o->data);
+ b_reset(o);
+ return num;
+}
+
+static FILE *generate_stream_from_list(struct pipe *head)
+{
+ FILE *pf;
+ int pid, channel[2];
+ if (pipe(channel) < 0) bb_perror_msg_and_die("pipe");
+#if !defined(__UCLIBC__) || defined(__ARCH_HAS_MMU__)
+ pid = fork();
+#else
+ pid = vfork();
+#endif
+ if (pid < 0) {
+ bb_perror_msg_and_die("fork");
+ } else if (pid == 0) {
+ close(channel[0]);
+ if (channel[1] != 1) {
+ dup2(channel[1],1);
+ close(channel[1]);
+ }
+ _exit(run_list_real(head)); /* leaks memory */
+ }
+ debug_printf("forked child %d\n",pid);
+ close(channel[1]);
+ pf = fdopen(channel[0],"r");
+ debug_printf("pipe on FILE *%p\n",pf);
+ return pf;
+}
+
+/* this version hacked for testing purposes */
+/* return code is exit status of the process that is run. */
+static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end)
+{
+ int retcode;
+ o_string result = NULL_O_STRING;
+ struct p_context inner;
+ FILE *p;
+ struct in_str pipe_str;
+ initialize_context(&inner);
+
+ /* recursion to generate command */
+ retcode = parse_stream(&result, &inner, input, subst_end);
+ if (retcode != 0) return retcode; /* syntax error or EOF */
+ done_word(&result, &inner);
+ done_pipe(&inner, PIPE_SEQ);
+ b_free(&result);
+
+ p = generate_stream_from_list(inner.list_head);
+ if (p == NULL) return 1;
+ mark_open(fileno(p));
+ setup_file_in_str(&pipe_str, p);
+
+ /* now send results of command back into original context */
+ retcode = parse_stream(dest, ctx, &pipe_str, '\0');
+ /* XXX In case of a syntax error, should we try to kill the child?
+ * That would be tough to do right, so just read until EOF. */
+ if (retcode == 1) {
+ while (b_getch(&pipe_str) != EOF)
+ /* discard */;
+ }
+
+ debug_printf("done reading from pipe, pclose()ing\n");
+ /* This is the step that wait()s for the child. Should be pretty
+ * safe, since we just read an EOF from its stdout. We could try
+ * to better, by using wait(), and keeping track of background jobs
+ * at the same time. That would be a lot of work, and contrary
+ * to the KISS philosophy of this program. */
+ mark_closed(fileno(p));
+ retcode = pclose(p);
+ free_pipe_list(inner.list_head,0);
+ debug_printf("pclosed, retcode=%d\n",retcode);
+ /* XXX this process fails to trim a single trailing newline */
+ return retcode;
+}
+
+static int parse_group(o_string *dest, struct p_context *ctx,
+ struct in_str *input, int ch)
+{
+ int rcode, endch = 0;
+ struct p_context sub;
+ struct child_prog *child = ctx->child;
+ if (child->argv) {
+ syntax();
+ return 1; /* syntax error, groups and arglists don't mix */
+ }
+ initialize_context(&sub);
+ switch (ch) {
+ case '(':
+ endch = ')';
+ child->subshell = 1;
+ break;
+ case '{':
+ endch = '}';
+ break;
+ default:
+ syntax(); /* really logic error */
+ }
+ rcode = parse_stream(dest,&sub,input,endch);
+ done_word(dest,&sub); /* finish off the final word in the subcontext */
+ done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
+ child->group = sub.list_head;
+ return rcode;
+ /* child remains "open", available for possible redirects */
+}
+
+/* basically useful version until someone wants to get fancier,
+ * see the bash man page under "Parameter Expansion" */
+static const char *lookup_param(const char *src)
+{
+ const char *p = NULL;
+ if (src) {
+ p = getenv(src);
+ if (!p)
+ p = get_local_var(src);
+ }
+ return p;
+}
+
+/* return code: 0 for OK, 1 for syntax error */
+static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
+{
+ int i, advance = 0;
+ char sep[] = " ";
+ int ch = input->peek(input); /* first character after the $ */
+ debug_printf("handle_dollar: ch=%c\n",ch);
+ if (isalpha(ch)) {
+ b_addchr(dest, SPECIAL_VAR_SYMBOL);
+ ctx->child->sp++;
+ while (ch = b_peek(input),isalnum(ch) || ch == '_') {
+ b_getch(input);
+ b_addchr(dest,ch);
+ }
+ b_addchr(dest, SPECIAL_VAR_SYMBOL);
+ } else if (isdigit(ch)) {
+ i = ch-'0'; /* XXX is $0 special? */
+ if (i < global_argc) {
+ parse_string(dest, ctx, global_argv[i]); /* recursion */
+ }
+ advance = 1;
+ } else switch (ch) {
+ case '$':
+ b_adduint(dest,getpid());
+ advance = 1;
+ break;
+ case '!':
+ if (last_bg_pid > 0) b_adduint(dest, last_bg_pid);
+ advance = 1;
+ break;
+ case '?':
+ b_adduint(dest,last_return_code);
+ advance = 1;
+ break;
+ case '#':
+ b_adduint(dest,global_argc ? global_argc-1 : 0);
+ advance = 1;
+ break;
+ case '{':
+ b_addchr(dest, SPECIAL_VAR_SYMBOL);
+ ctx->child->sp++;
+ b_getch(input);
+ /* XXX maybe someone will try to escape the '}' */
+ while (1) {
+ ch = b_getch(input);
+ if (ch == EOF || ch == '}')
+ break;
+ b_addchr(dest,ch);
+ }
+ if (ch != '}') {
+ syntax();
+ return 1;
+ }
+ b_addchr(dest, SPECIAL_VAR_SYMBOL);
+ break;
+ case '(':
+ b_getch(input);
+ process_command_subs(dest, ctx, input, ')');
+ break;
+ case '*':
+ sep[0] = ifs[0];
+ for (i = 1; i < global_argc; i++) {
+ parse_string(dest, ctx, global_argv[i]);
+ if (i+1 < global_argc)
+ parse_string(dest, ctx, sep);
+ }
+ break;
+ case '@':
+ case '-':
+ case '_':
+ /* still unhandled, but should be eventually */
+ bb_error_msg("unhandled syntax: $%c",ch);
+ return 1;
+ break;
+ default:
+ b_addqchr(dest,'$',dest->quote);
+ }
+ /* Eat the character if the flag was set. If the compiler
+ * is smart enough, we could substitute "b_getch(input);"
+ * for all the "advance = 1;" above, and also end up with
+ * a nice size-optimized program. Hah! That'll be the day.
+ */
+ if (advance) b_getch(input);
+ return 0;
+}
+
+int parse_string(o_string *dest, struct p_context *ctx, const char *src)
+{
+ struct in_str foo;
+ setup_string_in_str(&foo, src);
+ return parse_stream(dest, ctx, &foo, '\0');
+}
+
+/* return code is 0 for normal exit, 1 for syntax error */
+int parse_stream(o_string *dest, struct p_context *ctx,
+ struct in_str *input, int end_trigger)
+{
+ int ch, m;
+ int redir_fd;
+ redir_type redir_style;
+ int next;
+
+ /* Only double-quote state is handled in the state variable dest->quote.
+ * A single-quote triggers a bypass of the main loop until its mate is
+ * found. When recursing, quote state is passed in via dest->quote. */
+
+ debug_printf("parse_stream, end_trigger=%d\n",end_trigger);
+ while ((ch = b_getch(input)) != EOF) {
+ m = map[ch];
+ next = (ch == '\n') ? 0 : b_peek(input);
+ debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n",
+ ch, ch, m, dest->quote);
+ if (m == 0 || ((m == 1 || m == 2) && dest->quote)) {
+ b_addqchr(dest, ch, dest->quote);
+ continue;
+ }
+ if (m == 2) { /* unquoted IFS */
+ if (done_word(dest, ctx)) {
+ return 1;
+ }
+ /* If we aren't performing a substitution, treat a newline as a
+ * command separator. */
+ if (end_trigger != '\0' && ch == '\n')
+ done_pipe(ctx,PIPE_SEQ);
+ }
+ if (ch == end_trigger && !dest->quote && ctx->w == RES_NONE) {
+ debug_printf("leaving parse_stream (triggered)\n");
+ return 0;
+ }
+ if (m == 2)
+ continue;
+ switch (ch) {
+ case '#':
+ if (dest->length == 0 && !dest->quote) {
+ while (1) {
+ ch = b_peek(input);
+ if (ch == EOF || ch == '\n')
+ break;
+ b_getch(input);
+ }
+ } else {
+ b_addqchr(dest, ch, dest->quote);
+ }
+ break;
+ case '\\':
+ if (next == EOF) {
+ syntax();
+ return 1;
+ }
+ b_addqchr(dest, '\\', dest->quote);
+ b_addqchr(dest, b_getch(input), dest->quote);
+ break;
+ case '$':
+ if (handle_dollar(dest, ctx, input) != 0) return 1;
+ break;
+ case '\'':
+ dest->nonnull = 1;
+ while (1) {
+ ch = b_getch(input);
+ if (ch == EOF || ch == '\'')
+ break;
+ b_addchr(dest,ch);
+ }
+ if (ch == EOF) {
+ syntax();
+ return 1;
+ }
+ break;
+ case '"':
+ dest->nonnull = 1;
+ dest->quote = !dest->quote;
+ break;
+ case '`':
+ process_command_subs(dest, ctx, input, '`');
+ break;
+ case '>':
+ redir_fd = redirect_opt_num(dest);
+ done_word(dest, ctx);
+ redir_style = REDIRECT_OVERWRITE;
+ if (next == '>') {
+ redir_style = REDIRECT_APPEND;
+ b_getch(input);
+ } else if (next == '(') {
+ syntax(); /* until we support >(list) Process Substitution */
+ return 1;
+ }
+ setup_redirect(ctx, redir_fd, redir_style, input);
+ break;
+ case '<':
+ redir_fd = redirect_opt_num(dest);
+ done_word(dest, ctx);
+ redir_style = REDIRECT_INPUT;
+ if (next == '<') {
+ redir_style = REDIRECT_HEREIS;
+ b_getch(input);
+ } else if (next == '>') {
+ redir_style = REDIRECT_IO;
+ b_getch(input);
+ } else if (next == '(') {
+ syntax(); /* until we support <(list) Process Substitution */
+ return 1;
+ }
+ setup_redirect(ctx, redir_fd, redir_style, input);
+ break;
+ case ';':
+ done_word(dest, ctx);
+ done_pipe(ctx,PIPE_SEQ);
+ break;
+ case '&':
+ done_word(dest, ctx);
+ if (next == '&') {
+ b_getch(input);
+ done_pipe(ctx,PIPE_AND);
+ } else {
+ done_pipe(ctx,PIPE_BG);
+ }
+ break;
+ case '|':
+ done_word(dest, ctx);
+ if (next == '|') {
+ b_getch(input);
+ done_pipe(ctx,PIPE_OR);
+ } else {
+ /* we could pick up a file descriptor choice here
+ * with redirect_opt_num(), but bash doesn't do it.
+ * "echo foo 2| cat" yields "foo 2". */
+ done_command(ctx);
+ }
+ break;
+ case '(':
+ case '{':
+ if (parse_group(dest, ctx, input, ch) != 0)
+ return 1;
+ break;
+ case ')':
+ case '}':
+ syntax(); /* Proper use of this character caught by end_trigger */
+ return 1;
+ default:
+ syntax(); /* this is really an internal logic error */
+ return 1;
+ }
+ }
+ /* complain if quote? No, maybe we just finished a command substitution
+ * that was quoted. Example:
+ * $ echo "`cat foo` plus more"
+ * and we just got the EOF generated by the subshell that ran "cat foo"
+ * The only real complaint is if we got an EOF when end_trigger != '\0',
+ * that is, we were really supposed to get end_trigger, and never got
+ * one before the EOF. Can't use the standard "syntax error" return code,
+ * so that parse_stream_outer can distinguish the EOF and exit smoothly. */
+ debug_printf("leaving parse_stream (EOF)\n");
+ if (end_trigger != '\0') return -1;
+ return 0;
+}
+
+static void mapset(const char *set, int code)
+{
+ const unsigned char *s;
+ for (s = (const unsigned char *)set; *s; s++) map[(int)*s] = code;
+}
+
+static void update_ifs_map(void)
+{
+ /* char *ifs and char map[256] are both globals. */
+ ifs = getenv("IFS");
+ if (ifs == NULL) ifs = " \t\n";
+ /* Precompute a list of 'flow through' behavior so it can be treated
+ * quickly up front. Computation is necessary because of IFS.
+ * Special case handling of IFS == " \t\n" is not implemented.
+ * The map[] array only really needs two bits each, and on most machines
+ * that would be faster because of the reduced L1 cache footprint.
+ */
+ memset(map, 0, sizeof(map)); /* most characters flow through always */
+ mapset("\\$'\"`", 3); /* never flow through */
+ mapset("<>;&|(){}#", 1); /* flow through if quoted */
+ mapset(ifs, 2); /* also flow through if quoted */
+}
+
+/* most recursion does not come through here, the exception is
+ * from builtin_source() */
+int parse_stream_outer(struct in_str *inp, int flag)
+{
+
+ struct p_context ctx;
+ o_string temp = NULL_O_STRING;
+ int rcode;
+ do {
+ ctx.type = flag;
+ initialize_context(&ctx);
+ update_ifs_map();
+ if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING)) mapset(";$&|", 0);
+ inp->promptmode = 1;
+ rcode = parse_stream(&temp, &ctx, inp, '\n');
+ if (rcode != 1 && ctx.old_flag != 0) {
+ syntax();
+ }
+ if (rcode != 1 && ctx.old_flag == 0) {
+ done_word(&temp, &ctx);
+ done_pipe(&ctx,PIPE_SEQ);
+ run_list(ctx.list_head);
+ } else {
+ if (ctx.old_flag != 0) {
+ free(ctx.stack);
+ b_reset(&temp);
+ }
+ temp.nonnull = 0;
+ temp.quote = 0;
+ inp->p = NULL;
+ free_pipe_list(ctx.list_head,0);
+ }
+ b_free(&temp);
+ } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
+ return 0;
+}
+
+static int parse_string_outer(const char *s, int flag)
+{
+ struct in_str input;
+ setup_string_in_str(&input, s);
+ return parse_stream_outer(&input, flag);
+}
+
+static int parse_file_outer(FILE *f)
+{
+ int rcode;
+ struct in_str input;
+ setup_file_in_str(&input, f);
+ rcode = parse_stream_outer(&input, FLAG_PARSE_SEMICOLON);
+ return rcode;
+}
+
+/* Make sure we have a controlling tty. If we get started under a job
+ * aware app (like bash for example), make sure we are now in charge so
+ * we don't fight over who gets the foreground */
+static void setup_job_control(void)
+{
+ static pid_t shell_pgrp;
+ /* Loop until we are in the foreground. */
+ while (tcgetpgrp (shell_terminal) != (shell_pgrp = getpgrp ()))
+ kill (- shell_pgrp, SIGTTIN);
+
+ /* Ignore interactive and job-control signals. */
+ signal(SIGINT, SIG_IGN);
+ signal(SIGQUIT, SIG_IGN);
+ signal(SIGTERM, SIG_IGN);
+ signal(SIGTSTP, SIG_IGN);
+ signal(SIGTTIN, SIG_IGN);
+ signal(SIGTTOU, SIG_IGN);
+ signal(SIGCHLD, SIG_IGN);
+
+ /* Put ourselves in our own process group. */
+ setsid();
+ shell_pgrp = getpid();
+ setpgid(shell_pgrp, shell_pgrp);
+
+ /* Grab control of the terminal. */
+ tcsetpgrp(shell_terminal, shell_pgrp);
+}
+
+int hush_main(int argc, char **argv);
+int hush_main(int argc, char **argv)
+{
+ int opt;
+ FILE *input;
+ char **e = environ;
+
+#if ENABLE_FEATURE_EDITING
+ line_input_state = new_line_input_t(FOR_SHELL);
+#endif
+
+ /* XXX what should these be while sourcing /etc/profile? */
+ global_argc = argc;
+ global_argv = argv;
+
+ /* (re?) initialize globals. Sometimes hush_main() ends up calling
+ * hush_main(), therefore we cannot rely on the BSS to zero out this
+ * stuff. Reset these to 0 every time. */
+ ifs = NULL;
+ /* map[] is taken care of with call to update_ifs_map() */
+ fake_mode = 0;
+ interactive = 0;
+ close_me_head = NULL;
+ last_bg_pid = 0;
+ job_list = NULL;
+ last_jobid = 0;
+
+ /* Initialize some more globals to non-zero values */
+ set_cwd();
+ if (ENABLE_FEATURE_EDITING)
+ cmdedit_set_initial_prompt();
+ else PS1 = NULL;
+ PS2 = "> ";
+
+ /* initialize our shell local variables with the values
+ * currently living in the environment */
+ if (e) {
+ for (; *e; e++)
+ set_local_var(*e, 2); /* without call putenv() */
+ }
+
+ last_return_code = EXIT_SUCCESS;
+
+ if (argv[0] && argv[0][0] == '-') {
+ debug_printf("\nsourcing /etc/profile\n");
+ if ((input = fopen("/etc/profile", "r")) != NULL) {
+ mark_open(fileno(input));
+ parse_file_outer(input);
+ mark_closed(fileno(input));
+ fclose(input);
+ }
+ }
+ input = stdin;
+
+ while ((opt = getopt(argc, argv, "c:xif")) > 0) {
+ switch (opt) {
+ case 'c':
+ {
+ global_argv = argv+optind;
+ global_argc = argc-optind;
+ opt = parse_string_outer(optarg, FLAG_PARSE_SEMICOLON);
+ goto final_return;
+ }
+ break;
+ case 'i':
+ interactive++;
+ break;
+ case 'f':
+ fake_mode++;
+ break;
+ default:
+#ifndef BB_VER
+ fprintf(stderr, "Usage: sh [FILE]...\n"
+ " or: sh -c command [args]...\n\n");
+ exit(EXIT_FAILURE);
+#else
+ bb_show_usage();
+#endif
+ }
+ }
+ /* A shell is interactive if the `-i' flag was given, or if all of
+ * the following conditions are met:
+ * no -c command
+ * no arguments remaining or the -s flag given
+ * standard input is a terminal
+ * standard output is a terminal
+ * Refer to Posix.2, the description of the `sh' utility. */
+ if (argv[optind] == NULL && input == stdin
+ && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)
+ ) {
+ interactive++;
+ }
+
+ debug_printf("\ninteractive=%d\n", interactive);
+ if (interactive) {
+ /* Looks like they want an interactive shell */
+#if !ENABLE_FEATURE_SH_EXTRA_QUIET
+ printf( "\n\n%s hush - the humble shell v0.01 (testing)\n",
+ BB_BANNER);
+ printf( "Enter 'help' for a list of built-in commands.\n\n");
+#endif
+ setup_job_control();
+ }
+
+ if (argv[optind] == NULL) {
+ opt = parse_file_outer(stdin);
+ goto final_return;
+ }
+
+ debug_printf("\nrunning script '%s'\n", argv[optind]);
+ global_argv = argv + optind;
+ global_argc = argc - optind;
+ input = xfopen(argv[optind], "r");
+ opt = parse_file_outer(input);
+
+#if ENABLE_FEATURE_CLEAN_UP
+ fclose(input);
+ if (cwd && cwd != bb_msg_unknown)
+ free((char*)cwd);
+ {
+ struct variables *cur, *tmp;
+ for (cur = top_vars; cur; cur = tmp) {
+ tmp = cur->next;
+ if (!cur->flg_read_only) {
+ free((char*)cur->name);
+ free((char*)cur->value);
+ free(cur);
+ }
+ }
+ }
+#endif
+
+final_return:
+ return opt ? opt : last_return_code;
+}
+
+static char *insert_var_value(char *inp)
+{
+ int res_str_len = 0;
+ int len;
+ int done = 0;
+ char *p, *res_str = NULL;
+ const char *p1;
+
+ while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
+ if (p != inp) {
+ len = p - inp;
+ res_str = xrealloc(res_str, (res_str_len + len));
+ strncpy((res_str + res_str_len), inp, len);
+ res_str_len += len;
+ }
+ inp = ++p;
+ p = strchr(inp, SPECIAL_VAR_SYMBOL);
+ *p = '\0';
+ p1 = lookup_param(inp);
+ if (p1) {
+ len = res_str_len + strlen(p1);
+ res_str = xrealloc(res_str, (1 + len));
+ strcpy((res_str + res_str_len), p1);
+ res_str_len = len;
+ }
+ *p = SPECIAL_VAR_SYMBOL;
+ inp = ++p;
+ done = 1;
+ }
+ if (done) {
+ res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
+ strcpy((res_str + res_str_len), inp);
+ while ((p = strchr(res_str, '\n'))) {
+ *p = ' ';
+ }
+ }
+ return (res_str == NULL) ? inp : res_str;
+}
+
+static char **make_list_in(char **inp, char *name)
+{
+ int len, i;
+ int name_len = strlen(name);
+ int n = 0;
+ char **list;
+ char *p1, *p2, *p3;
+
+ /* create list of variable values */
+ list = xmalloc(sizeof(*list));
+ for (i = 0; inp[i]; i++) {
+ p3 = insert_var_value(inp[i]);
+ p1 = p3;
+ while (*p1) {
+ if ((*p1 == ' ')) {
+ p1++;
+ continue;
+ }
+ if ((p2 = strchr(p1, ' '))) {
+ len = p2 - p1;
+ } else {
+ len = strlen(p1);
+ p2 = p1 + len;
+ }
+ /* we use n + 2 in realloc for list,because we add
+ * new element and then we will add NULL element */
+ list = xrealloc(list, sizeof(*list) * (n + 2));
+ list[n] = xmalloc(2 + name_len + len);
+ strcpy(list[n], name);
+ strcat(list[n], "=");
+ strncat(list[n], p1, len);
+ list[n++][name_len + len + 1] = '\0';
+ p1 = p2;
+ }
+ if (p3 != inp[i]) free(p3);
+ }
+ list[n] = NULL;
+ return list;
+}
+
+/* Make new string for parser */
+static char* make_string(char ** inp)
+{
+ char *p;
+ char *str = NULL;
+ int n;
+ int len = 2;
+
+ for (n = 0; inp[n]; n++) {
+ p = insert_var_value(inp[n]);
+ str = xrealloc(str, (len + strlen(p)));
+ if (n) {
+ strcat(str, " ");
+ } else {
+ *str = '\0';
+ }
+ strcat(str, p);
+ len = strlen(str) + 3;
+ if (p != inp[n]) free(p);
+ }
+ len = strlen(str);
+ *(str + len) = '\n';
+ *(str + len + 1) = '\0';
+ return str;
+}