diff options
Diffstat (limited to 'src/pushd.c')
-rw-r--r-- | src/pushd.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/src/pushd.c b/src/pushd.c new file mode 100644 index 0000000..6de10a6 --- /dev/null +++ b/src/pushd.c @@ -0,0 +1,162 @@ +/* wydawca - automatic release submission daemon + Copyright (C) 2011 Sergey Poznyakoff + + Wydawca 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 3 of the License, or (at your + option) any later version. + + Wydawca 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 wydawca. If not, see <http://www.gnu.org/licenses/>. */ + +#include "wydawca.h" + +struct saved_dir +{ + struct saved_dir *prev; + int fd; + char *name; +}; + +struct saved_dir *dir_stack; + +#ifndef O_SEARCH +# define O_SEARCH 0 +#endif + +char * +getcwd_alloc (void) +{ + size_t size = 0; + char *buf = NULL; + char *p; + + do + { + if (!buf) + { + size = 64; + buf = malloc (size); + } + else + { + char *np; + size_t ns = 2 * size; + if (ns < size) + { + free (buf); + errno = ENOMEM; + return NULL; + } + size = ns; + np = realloc (buf, size); + if (!np) + free (buf); + buf = np; + } + if (!buf) + return NULL; + } + while ((p = getcwd (buf, size)) == NULL && errno == ERANGE); + if (!p) + { + int ec = errno; + free (buf); + buf = NULL; + errno = ec; + } + return buf; +} + +static int +_save_dir (struct saved_dir *sd) +{ + int fd; + +#ifdef HAVE_FCHDIR + fd = open (".", O_SEARCH); +#else + fd = -1; +#endif + if (fd == -1) + { + sd->name = getcwd_alloc (); + if (!sd->name) + return errno; + } + else + sd->name = NULL; + sd->fd = fd; + return 0; +} + +static void +_drop_dir (struct saved_dir *sd) +{ + if (sd->fd != -1) + close (sd->fd); + free (sd->name); + free (sd); +} + +static int +_push_dir (struct saved_dir *sd, const char *dirname) +{ + int rc = _save_dir (sd); + if (rc) + return rc; + if (dirname && chdir (dirname)) + { + rc = errno; + _drop_dir (sd); + return rc; + } + return 0; +} + +int +push_dir (const char *dirname) +{ + int rc; + struct saved_dir *sd = malloc (sizeof (*sd)); + + if (!sd) + return errno; + rc = _push_dir (sd, dirname); + if (rc) + { + errno = rc; + return -1; + } + sd->prev = dir_stack; + dir_stack = sd; + return 0; +} + +int +pop_dir () +{ + struct saved_dir *sd = dir_stack; + int rc; + + if (!sd) + { + errno = ENOENT; + return -1; + } + dir_stack = sd->prev; + if (sd->fd != -1) + rc = fchdir (sd->fd); + else + rc = chdir (sd->name); + if (rc) + rc = errno; + _drop_dir (sd); + errno = rc; + return rc; +} |