summaryrefslogtreecommitdiff
path: root/i/pc104/initrd/conf/busybox/libbb/process_escape_sequence.c
diff options
context:
space:
mode:
Diffstat (limited to 'i/pc104/initrd/conf/busybox/libbb/process_escape_sequence.c')
-rw-r--r--i/pc104/initrd/conf/busybox/libbb/process_escape_sequence.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/i/pc104/initrd/conf/busybox/libbb/process_escape_sequence.c b/i/pc104/initrd/conf/busybox/libbb/process_escape_sequence.c
new file mode 100644
index 0000000..138e751
--- /dev/null
+++ b/i/pc104/initrd/conf/busybox/libbb/process_escape_sequence.c
@@ -0,0 +1,89 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) Manuel Novoa III <mjn3@codepoet.org>
+ * and Vladimir Oleynik <dzo@simtreas.ru>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include <stdio.h>
+#include <limits.h>
+#include <ctype.h>
+#include "libbb.h"
+
+#define WANT_HEX_ESCAPES 1
+
+/* Usual "this only works for ascii compatible encodings" disclaimer. */
+#undef _tolower
+#define _tolower(X) ((X)|((char) 0x20))
+
+char bb_process_escape_sequence(const char **ptr)
+{
+ static const char charmap[] = {
+ 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', 0,
+ '\a', '\b', '\f', '\n', '\r', '\t', '\v', '\\', '\\' };
+
+ const char *p;
+ const char *q;
+ unsigned int num_digits;
+ unsigned int r;
+ unsigned int n;
+ unsigned int d;
+ unsigned int base;
+
+ num_digits = n = 0;
+ base = 8;
+ q = *ptr;
+
+#ifdef WANT_HEX_ESCAPES
+ if (*q == 'x') {
+ ++q;
+ base = 16;
+ ++num_digits;
+ }
+#endif
+
+ do {
+ d = (unsigned int)(*q - '0');
+#ifdef WANT_HEX_ESCAPES
+ if (d >= 10) {
+ d = ((unsigned int)(_tolower(*q) - 'a')) + 10;
+ }
+#endif
+
+ if (d >= base) {
+#ifdef WANT_HEX_ESCAPES
+ if ((base == 16) && (!--num_digits)) {
+/* return '\\'; */
+ --q;
+ }
+#endif
+ break;
+ }
+
+ r = n * base + d;
+ if (r > UCHAR_MAX) {
+ break;
+ }
+
+ n = r;
+ ++q;
+ } while (++num_digits < 3);
+
+ if (num_digits == 0) { /* mnemonic escape sequence? */
+ p = charmap;
+ do {
+ if (*p == *q) {
+ q++;
+ break;
+ }
+ } while (*++p);
+ n = *(p+(sizeof(charmap)/2));
+ }
+
+ *ptr = q;
+
+ return (char) n;
+}