//========================================================================== // // misc.cxx // // Fileio miscellaneous functions // //========================================================================== //####ECOSGPLCOPYRIGHTBEGIN#### // ------------------------------------------- // This file is part of eCos, the Embedded Configurable Operating System. // Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc. // Copyright (C) 2003 Gary Thomas // // eCos is free software; you can redistribute it and/or modify it under // the terms of the GNU General Public License as published by the Free // Software Foundation; either version 2 or (at your option) any later version. // // eCos is distributed in the hope that it will be useful, but WITHOUT ANY // WARRANTY; without even the implied warranty of MERCHANTABILITY or // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License // for more details. // // You should have received a copy of the GNU General Public License along // with eCos; if not, write to the Free Software Foundation, Inc., // 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. // // As a special exception, if other files instantiate templates or use macros // or inline functions from this file, or you compile this file and link it // with other works to produce a work based on this file, this file does not // by itself cause the resulting work to be covered by the GNU General Public // License. However the source code for this file must still be made available // in accordance with section (3) of the GNU General Public License. // // This exception does not invalidate any other reasons why a work based on // this file might be covered by the GNU General Public License. // // Alternative licenses for eCos may be arranged by contacting Red Hat, Inc. // at http://sources.redhat.com/ecos/ecos-license/ // ------------------------------------------- //####ECOSGPLCOPYRIGHTEND#### //========================================================================== //#####DESCRIPTIONBEGIN#### // // Author(s): nickg // Contributors: nickg // Date: 2000-05-25 // Purpose: Fileio miscellaneous functions // Description: This file contains various miscellaneous functions // for use with the fileio system. These include startup, // table management, and other service routines. // //####DESCRIPTIONEND#### // //========================================================================== #include #include #include #ifdef CYGPKG_LIBC_TIME #include #endif #include // tracing macros #include // assertion macros #include // strcmp() #include // time() #ifdef CYGPKG_IO_WALLCLOCK # include // Wallclock class #endif #ifdef CYGPKG_KERNEL #include #include // base kernel types #include // Clock inlines #endif #include "fio.h" // Private header //========================================================================== // forward definitions static void cyg_mtab_init(); __externC int chdir( const char *path ); //========================================================================== // Filesystem tables // ------------------------------------------------------------------------- // Filesystem table. // This array contains entries for all filesystem that are installed in // the system. __externC cyg_fstab_entry cyg_fstab[]; CYG_HAL_TABLE_BEGIN( cyg_fstab, fstab ); // end of filesystem table, set in linker script. __externC cyg_fstab_entry cyg_fstab_end; CYG_HAL_TABLE_END( cyg_fstab_end, fstab ); #ifdef CYGPKG_KERNEL // Array of mutexes for locking the fstab entries static Cyg_Mutex fstab_lock[CYGNUM_FILEIO_FSTAB_MAX] CYGBLD_ATTRIB_INIT_PRI(CYG_INIT_IO_FS); #endif // ------------------------------------------------------------------------- // Mount table. // This array contains entries for all valid running filesystems. __externC cyg_mtab_entry cyg_mtab[]; CYG_HAL_TABLE_BEGIN( cyg_mtab, mtab ); // Extra entries at end of mtab for dynamic mount points. cyg_mtab_entry cyg_mtab_extra[CYGNUM_FILEIO_MTAB_EXTRA] CYG_HAL_TABLE_EXTRA(mtab) = { { NULL } }; // End of mount table, set in the linker script. __externC cyg_mtab_entry cyg_mtab_end; CYG_HAL_TABLE_END( cyg_mtab_end, mtab ); #ifdef CYGPKG_KERNEL // Array of mutexes for locking the mtab entries static Cyg_Mutex mtab_lock[CYGNUM_FILEIO_MTAB_MAX] CYGBLD_ATTRIB_INIT_PRI(CYG_INIT_IO_FS); #endif //========================================================================== // Current directory cyg_mtab_entry *cyg_cdir_mtab_entry = NULL; cyg_dir cyg_cdir_dir = CYG_DIR_NULL; //========================================================================== // Initialization object class Cyg_Fileio_Init_Class { public: Cyg_Fileio_Init_Class(); }; static Cyg_Fileio_Init_Class fileio_initializer CYGBLD_ATTRIB_INIT_PRI(CYG_INIT_IO_FS); Cyg_Fileio_Init_Class::Cyg_Fileio_Init_Class() { cyg_fd_init(); cyg_mtab_init(); chdir("/"); } //========================================================================== // Mount table initializer static void cyg_mtab_init() { cyg_mtab_entry *m; for( m = &cyg_mtab[0]; m != &cyg_mtab_end; m++ ) { const char *fsname = m->fsname; cyg_fstab_entry *f; // Ignore empty entries if( m->name == NULL ) continue; // stop if there are more than the configured maximum if( m-&cyg_mtab[0] >= CYGNUM_FILEIO_MTAB_MAX ) break; for( f = &cyg_fstab[0]; f != &cyg_fstab_end; f++ ) { // stop if there are more than the configured maximum if( f-&cyg_fstab[0] >= CYGNUM_FILEIO_FSTAB_MAX ) break; if( strcmp( fsname, f->name) == 0 ) { // We have a match. if( f->mount( f, m ) == 0 ) { m->valid = true; m->fs = f; // m->root installed by fs. } else { m->valid = false; } break; } } } } //========================================================================== // Mount table matching // ------------------------------------------------------------------------- // matchlen() compares two strings and returns the number of bytes by which // they match. static int matchlen( const char *s1, const char *s2 ) { int len = 0; while( s1[len] == s2[len] && s1[len] && s2[len] ) len++; // Return length only if s2 is an initial substring of s1, // and it terminates in s1 at end-of-string or a '/'. // Special case for s2 == "/" if( len == 1 && s2[0] == '/' && s2[1] == 0 ) return len; if( (s2[len] == 0) && (s1[len] == 0 || s1[len] == '/')) return len; else return 0; } // ------------------------------------------------------------------------- // Search the mtab for the entry that matches the longest substring of // **name. __externC int cyg_mtab_lookup( cyg_dir *dir, const char **name, cyg_mtab_entry **mte) { cyg_mtab_entry *m, *best = NULL; int best_len = 0; // Unrooted file names go straight to current dir if( **name != '/' ) { if (*mte == (cyg_mtab_entry *)NULL) { // No known current directory return -1; } // Current directory is well known return 0; } // Otherwise search the mount table. for( m = &cyg_mtab[0]; m != &cyg_mtab_end; m++ ) { if( m->name != NULL && m->valid ) { int len = matchlen(*name,m->name); if( len > best_len ) best = m, best_len = len; } } // No match found, bad path name... if( best_len == 0 ) return -1; *name += best_len; if( **name == '/' ) (*name)++; *mte = best; *dir = best->root; return 0; } //========================================================================== // mount filesystem __externC int mount( const char *devname, const char *dir, const char *fsname) { FILEIO_ENTRY(); cyg_mtab_entry *m; cyg_fstab_entry *f; int result = ENOERR; // Search the mount table for an empty entry for( m = &cyg_mtab[0]; m != &cyg_mtab_end; m++ ) { // stop if there are more than the configured maximum if( m-&cyg_mtab[0] >= CYGNUM_FILEIO_MTAB_MAX ) { m = &cyg_mtab_end; break; } if( m->name == NULL ) break; } if( m == &cyg_mtab_end ) FILEIO_RETURN(ENOMEM); // Now search the fstab for the filesystem implementation for( f = &cyg_fstab[0]; f != &cyg_fstab_end; f++ ) { // stop if there are more than the configured maximum if( f-&cyg_fstab[0] >= CYGNUM_FILEIO_FSTAB_MAX ) break; if( strcmp( fsname, f->name) == 0 ) break; } if( f == &cyg_fstab_end ) FILEIO_RETURN(ENODEV); // We have a match. m->name = dir; m->fsname = fsname; m->devname = devname; if( (result = f->mount( f, m )) == 0 ) { m->valid = true; m->fs = f; // m->root installed by fs. } else { m->valid = false; m->name = NULL; } // Make sure that there is something to search (for open) if (cyg_cdir_mtab_entry == (cyg_mtab_entry *)NULL) { cyg_cdir_mtab_entry = m; } FILEIO_RETURN(result); } //========================================================================== // unmount filesystem __externC int umount( const char *name) { int err = ENOERR; FILEIO_ENTRY(); cyg_mtab_entry *m; // Search the mount table for a matching entry for( m = &cyg_mtab[0]; m != &cyg_mtab_end; m++ ) { // stop if there are more than the configured maximum if( m-&cyg_mtab[0] >= CYGNUM_FILEIO_MTAB_MAX ) { m = &cyg_mtab_end; break; } // Ignore empty or invalid entries if( m->name == NULL || !m->valid ) continue; // match names. if( strcmp(name,m->name) == 0 ) break; // Match device name too? } if( m == &cyg_mtab_end ) FILEIO_RETURN(EINVAL); // We have a match, call the umount function err = m->fs->umount( m ); if( err == ENOERR ) { m->valid = false; m->name = NULL; } FILEIO_RETURN(err); } //========================================================================== // Implement filesystem locking protocol. void cyg_fs_lock( cyg_mtab_entry *mte, cyg_uint32 syncmode ) { CYG_ASSERT(mte != NULL, "Bad mount table entry"); if( syncmode & CYG_SYNCMODE_FILE_FILESYSTEM ) { CYG_ASSERT(mte->fs-&cyg_fstab[0] < CYGNUM_FILEIO_FSTAB_MAX, "Bad file system"); FILEIO_MUTEX_LOCK( fstab_lock[mte->fs-&cyg_fstab[0]] ); } if( syncmode & CYG_SYNCMODE_FILE_MOUNTPOINT ) { CYG_ASSERT(mte-&cyg_mtab[0] < CYGNUM_FILEIO_MTAB_MAX, "Bad mount point"); FILEIO_MUTEX_LOCK( mtab_lock[mte-&cyg_mtab[0]] ); } } void cyg_fs_unlock( cyg_mtab_entry *mte, cyg_uint32 syncmode ) { CYG_ASSERT(mte != NULL, "Bad mount table entry"); if( syncmode & CYG_SYNCMODE_FILE_FILESYSTEM ) { CYG_ASSERT(mte->fs-&cyg_fstab[0] < CYGNUM_FILEIO_FSTAB_MAX, "Bad file system"); FILEIO_MUTEX_UNLOCK( fstab_lock[mte->fs-&cyg_fstab[0]] ); } if( syncmode & CYG_SYNCMODE_FILE_MOUNTPOINT ) { CYG_ASSERT(mte-&cyg_mtab[0] < CYGNUM_FILEIO_MTAB_MAX, "Bad mount point"); FILEIO_MUTEX_UNLOCK( mtab_lock[mte-&cyg_mtab[0]] ); } } //========================================================================== // Search mount table for a filesystems root. __externC cyg_mtab_entry * cyg_fs_root_lookup( cyg_dir *root ) { cyg_mtab_entry *m; for( m = &cyg_mtab[0]; m != &cyg_mtab_end; m++ ) { if( (cyg_dir *)m->root == root ) { return m; } } return NULL; } //========================================================================== // Timestamp support // This provides access to the current time/date, expressed as a // time_t. It uses a number of mechanisms to do this, selecting // whichever is available in the current configuration. __externC time_t cyg_timestamp() { #if defined(CYGPKG_IO_WALLCLOCK) // First, try to get the time from the wallclock device. return (time_t) Cyg_WallClock::wallclock->get_current_time(); #elif defined(CYGINT_ISO_POSIX_TIMERS) // If POSIX is present, use the current value of the realtime // clock. struct timespec tp; clock_gettime( CLOCK_REALTIME, &tp ); return (time_t) tp.tv_sec; #elif defined(CYGPKG_KERNEL) // If all else fails, get the current realtime clock value and // convert it to seconds ourself. static struct Cyg_Clock::converter sec_converter; static cyg_bool initialized = false; cyg_tick_count ticks; if( !initialized ) { Cyg_Clock::real_time_clock->get_clock_to_other_converter( 1000000000, &sec_converter ); initialized = true; } ticks = Cyg_Clock::real_time_clock->current_value(); return (time_t) Cyg_Clock::convert( ticks, &sec_converter ); #else /* No clock support at all. */ return (time_t) 0; #endif } //========================================================================== // Default functions __externC int cyg_fileio_enosys() { return ENOSYS; } __externC int cyg_fileio_erofs() { return EROFS; } __externC int cyg_fileio_enoerr() { return ENOERR; } __externC int cyg_fileio_enotdir() { return ENOTDIR; } __externC cyg_bool cyg_fileio_seltrue (struct CYG_FILE_TAG *fp, int which, CYG_ADDRWORD info) { return 1; } // ------------------------------------------------------------------------- // EOF misc.cxx