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-rw-r--r--io/ftw.c585
1 files changed, 448 insertions, 137 deletions
diff --git a/io/ftw.c b/io/ftw.c
index d7ec716936..e20ad231d3 100644
--- a/io/ftw.c
+++ b/io/ftw.c
@@ -1,6 +1,7 @@
-/* Copyright (C) 1992, 1995, 1996, 1997 Free Software Foundation, Inc.
+/* File tree walker functions.
+ Copyright (C) 1996, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
- Contributed by Ian Lance Taylor (ian@airs.com).
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
@@ -17,197 +18,507 @@
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
+#include <dirent.h>
#include <errno.h>
-#include <limits.h>
+#include <ftw.h>
+#include <search.h>
#include <stdlib.h>
#include <string.h>
-#include <dirent.h>
-#include <sys/types.h>
+#include <unistd.h>
+#include <sys/param.h>
#include <sys/stat.h>
-#include <ftw.h>
+/* #define NDEBUG 1 */
+#include <assert.h>
-#ifndef PATH_MAX
-#define PATH_MAX 1024 /* XXX */
-#endif
+struct dir_data
+{
+ DIR *stream;
+ char *content;
+};
-/* Traverse one level of a directory tree. */
-
-static int
-ftw_dir (DIR **dirs, int level, int descriptors, char *dir, size_t len,
- int (*func) (const char *file, const struct stat *status, int flag))
+struct ftw_data
{
- int got;
- struct dirent *entry;
+ struct dir_data **dirstreams;
+ size_t actdir;
+ size_t maxdir;
- got = 0;
+ char *dirbuf;
+ size_t dirbufsize;
+ struct FTW ftw;
- __set_errno (0);
+ int flags;
- while ((entry = readdir (dirs[level])) != NULL)
- {
- struct stat s;
- int flag, retval, newlev;
- size_t namlen;
+ int *cvt_arr;
+ __nftw_func_t func;
- ++got;
+ struct stat st;
- if (entry->d_name[0] == '.'
- && (entry->d_name[1] == '\0' ||
- (entry->d_name[1] == '.' && entry->d_name[2] == '\0')))
- {
- __set_errno (0);
- continue;
- }
+ dev_t dev;
+};
- namlen = _D_EXACT_NAMLEN (entry);
- if (namlen + len + 1 > PATH_MAX)
- {
-#ifdef ENAMETOOLONG
- __set_errno (ENAMETOOLONG);
-#else
- __set_errno (ENOMEM);
-#endif
- return -1;
- }
+/* Internally we use the FTW_* constants used for `nftw'. When the
+ process called `ftw' we must reduce the flag to the known flags
+ for `ftw'. */
+static int nftw_arr[] =
+{
+ FTW_F, FTW_D, FTW_DNR, FTW_NS, FTW_SL, FTW_DP, FTW_SLN
+};
- dir[len] = '/';
- memcpy ((void *) (dir + len + 1), (void *) entry->d_name,
- namlen + 1);
+static int ftw_arr[] =
+{
+ FTW_F, FTW_D, FTW_DNR, FTW_NS, FTW_F, FTW_D, FTW_NS
+};
- if (stat (dir, &s) < 0)
- {
- if (errno != EACCES && errno != ENOENT)
- return -1;
- flag = FTW_NS;
- }
- else if (S_ISDIR (s.st_mode))
+
+/* Forward declarations of local functions. */
+static int ftw_dir (struct ftw_data *data);
+
+
+static inline int
+open_dir_stream (struct ftw_data *data, struct dir_data *dirp)
+{
+ int result = 0;
+
+ if (data->dirstreams[data->actdir] != NULL)
+ {
+ /* Oh, oh. We must close this stream. Get all remaining
+ entries and store them as a list in the `content' member of
+ the `struct dir_data' variable. */
+ size_t bufsize = 1024;
+ char *buf = malloc (bufsize);
+
+ if (buf == NULL)
+ result = -1;
+ else
{
- newlev = (level + 1) % descriptors;
+ DIR *st = data->dirstreams[data->actdir]->stream;
+ struct dirent *d;
+ size_t actsize = 0;
+
+ while ((d = readdir (st)) != NULL)
+ {
+ size_t this_len = _D_EXACT_NAMLEN (d);
+ if (actsize + this_len + 2 >= bufsize)
+ {
+ char *newp;
+ bufsize += MAX (1024, 2 * this_len);
+ newp = realloc (buf, bufsize);
+ if (newp == NULL)
+ {
+ /* No more memory. */
+ int save_err = errno;
+ free (buf);
+ __set_errno (save_err);
+ result = -1;
+ break;
+ }
+ buf = newp;
+ }
+
+ memcpy (buf + actsize, d->d_name, this_len);
+ actsize += this_len;
+ buf[actsize++] = '\0';
+ }
- if (dirs[newlev] != NULL)
- closedir (dirs[newlev]);
+ /* Terminate the list with an additional NUL byte. */
+ buf[actsize++] = '\0';
- dirs[newlev] = opendir (dir);
- if (dirs[newlev] != NULL)
- flag = FTW_D;
+ /* Shrink the buffer to what we actually need. */
+ data->dirstreams[data->actdir]->content = realloc (buf, actsize);
+ if (data->dirstreams[data->actdir]->content == NULL)
+ {
+ int save_err = errno;
+ free (buf);
+ __set_errno (save_err);
+ result = -1;
+ }
else
{
- if (errno != EACCES)
- return -1;
- flag = FTW_DNR;
+ closedir (st);
+ data->dirstreams[data->actdir]->stream = NULL;
+ data->dirstreams[data->actdir] = NULL;
}
}
+ }
+
+ /* Open the new stream. */
+ if (result == 0)
+ {
+ assert (data->dirstreams[data->actdir] == NULL);
+
+ dirp->stream = opendir (data->dirbuf);
+ if (dirp->stream == NULL)
+ result = -1;
else
- flag = FTW_F;
+ {
+ dirp->content = NULL;
+ data->dirstreams[data->actdir] = dirp;
+
+ if (++data->actdir == data->maxdir)
+ data->actdir = 0;
+ }
+ }
+
+ return result;
+}
+
+
+static inline int
+process_entry (struct ftw_data *data, struct dir_data *dir, const char *name,
+ size_t namlen)
+{
+ int result = 0;
+ int flag;
+
+ if (name[0] == '.' && (name[1] == '\0'
+ || (name[1] == '.' && name[2] == '\0')))
+ /* Don't process the "." and ".." entries. */
+ return 0;
+
+ if (data->dirbufsize < data->ftw.base + namlen + 2)
+ {
+ /* Enlarge the buffer. */
+ char *newp;
+
+ data->dirbufsize *= 2;
+ newp = realloc (data->dirbuf, data->dirbufsize);
+ if (newp == NULL)
+ return -1;
+ data->dirbuf = newp;
+ }
- retval = (*func) (dir, &s, flag);
+ memcpy (data->dirbuf + data->ftw.base, name, namlen);
+ data->dirbuf[data->ftw.base + namlen] = '\0';
+ if (((data->flags & FTW_PHYS) ? lstat : stat) (data->dirbuf, &data->st) < 0)
+ {
+ if (errno != EACCES && errno != ENOENT)
+ result = -1;
+ else if (!(data->flags & FTW_PHYS)
+ && lstat (data->dirbuf, &data->st) == 0
+ && S_ISLNK (data->st.st_mode))
+ flag = FTW_SLN;
+ else
+ flag = FTW_NS;
+ }
+ else
+ {
+ if (S_ISDIR (data->st.st_mode))
+ flag = FTW_D;
+ else if (S_ISLNK (data->st.st_mode))
+ flag = FTW_SL;
+ else
+ flag = FTW_F;
+ }
+
+ if (result == 0
+ && (!(data->flags & FTW_MOUNT) || data->st.st_dev == data->dev))
+ {
if (flag == FTW_D)
{
- if (retval == 0)
- retval = ftw_dir (dirs, newlev, descriptors, dir,
- namlen + len + 1, func);
- if (dirs[newlev] != NULL)
- {
- int save;
+ result = ftw_dir (data);
- save = errno;
- closedir (dirs[newlev]);
- __set_errno (save);
- dirs[newlev] = NULL;
+ if (result == 0 && (data->flags & FTW_CHDIR))
+ {
+ /* Change back to current directory. */
+ int done = 0;
+ if (dir->stream != NULL)
+ if (fchdir (dirfd (dir->stream)) == 0)
+ done = 1;
+
+ if (!done)
+ {
+ if (data->ftw.base == 1)
+ {
+ if (chdir ("/") < 0)
+ result = -1;
+ }
+ else
+ {
+ /* Please note that we overwrite a slash. */
+ data->dirbuf[data->ftw.base - 1] = '\0';
+
+ if (chdir (data->dirbuf) < 0)
+ result = -1;
+ else
+ data->dirbuf[data->ftw.base - 1] = '/';
+ }
+ }
}
}
+ else
+ result = (*data->func) (data->dirbuf, &data->st, data->cvt_arr[flag],
+ &data->ftw);
+ }
+
+ return result;
+}
+
+
+static int
+ftw_dir (struct ftw_data *data)
+{
+ struct dir_data dir;
+ struct dirent *d;
+ int previous_base = data->ftw.base;
+ int result = 0;
+ char *startp;
+
+ /* First, report the directory (if not depth-first). */
+ if (!(data->flags & FTW_DEPTH))
+ {
+ result = (*data->func) (data->dirbuf, &data->st, FTW_D, &data->ftw);
+ if (result != 0)
+ return result;
+ }
- if (retval != 0)
- return retval;
+ /* Open the stream for this directory. This might require that
+ another stream has to be closed. */
+ result = open_dir_stream (data, &dir);
+ if (result != 0)
+ return result;
- if (dirs[level] == NULL)
+ /* If necessary, change to this directory. */
+ if (data->flags & FTW_CHDIR)
+ {
+ if (fchdir (dirfd (dir.stream)) < 0)
{
- int skip;
-
- dir[len] = '\0';
- dirs[level] = opendir (dir);
- if (dirs[level] == NULL)
- return -1;
- skip = got;
- while (skip-- != 0)
+ if (errno == ENOSYS)
{
- __set_errno (0);
- if (readdir (dirs[level]) == NULL)
- return errno == 0 ? 0 : -1;
+ if (chdir (data->dirbuf) < 0)
+ result = -1;
}
+ else
+ result = -1;
}
- __set_errno (0);
+ if (result != 0)
+ {
+ int save_err = errno;
+ closedir (dir.stream);
+ __set_errno (save_err);
+
+ if (data->actdir-- == 0)
+ data->actdir = data->maxdir - 1;
+ data->dirstreams[data->actdir] = NULL;
+
+ return result;
+ }
}
- return errno == 0 ? 0 : -1;
-}
+ /* Next, update the `struct FTW' information. */
+ ++data->ftw.level;
+ startp = strchr (data->dirbuf, '\0');
+ *startp++ = '/';
+ data->ftw.base = startp - data->dirbuf;
-/* Call a function on every element in a directory tree. */
+ while (dir.stream != NULL && (d = readdir (dir.stream)) != NULL)
+ {
+ result = process_entry (data, &dir, d->d_name, _D_EXACT_NAMLEN (d));
+ if (result != 0)
+ break;
+ }
-int
-ftw (const char *dir,
- int (*func) (const char *file, const struct stat *status, int flag),
- int descriptors)
-{
- DIR **dirs;
- size_t len;
- char buf[PATH_MAX + 1];
- struct stat s;
- int flag, retval;
- int i;
-
- if (descriptors <= 0)
- descriptors = 1;
-
- dirs = (DIR **) __alloca (descriptors * sizeof (DIR *));
- i = descriptors;
- while (i-- > 0)
- dirs[i] = NULL;
-
- if (stat (dir, &s) < 0)
+ if (dir.stream != NULL)
{
- if (errno != EACCES && errno != ENOENT)
- return -1;
- flag = FTW_NS;
+ /* The stream is still open. I.e., we did not need more
+ descriptors. Simply close the stream now. */
+ int save_err = errno;
+
+ assert (dir.content == NULL);
+
+ closedir (dir.stream);
+ __set_errno (save_err);
+
+ if (data->actdir-- == 0)
+ data->actdir = data->maxdir - 1;
+ data->dirstreams[data->actdir] = NULL;
}
- else if (S_ISDIR (s.st_mode))
+ else
{
- dirs[0] = opendir (dir);
- if (dirs[0] != NULL)
- flag = FTW_D;
- else
+ int save_err;
+ char *runp = dir.content;
+
+ assert (result == 0);
+
+ while (*runp != '\0')
{
- if (errno != EACCES)
- return -1;
- flag = FTW_DNR;
+ char *endp = strchr (runp, '\0');
+
+ result = process_entry (data, &dir, runp, endp - runp);
+ if (result != 0)
+ break;
+
+ runp = endp + 1;
}
+
+ save_err = errno;
+ free (dir.content);
+ __set_errno (save_err);
}
- else
- flag = FTW_F;
- len = strlen (dir);
- memcpy ((void *) buf, (void *) dir, len + 1);
+ /* Prepare the return, revert the `struct FTW' information. */
+ --data->ftw.level;
+ data->ftw.base = previous_base;
+
+ /* Finally, if we process depth-first report the directory. */
+ if (result == 0 && (data->flags & FTW_DEPTH))
+ result = (*data->func) (data->dirbuf, &data->st, FTW_DP, &data->ftw);
- retval = (*func) (buf, &s, flag);
+ return result;
+}
+
+
+static int
+ftw_startup (const char *dir, int is_nftw, void *func, int descriptors,
+ int flags)
+{
+ struct ftw_data data;
+ int result = 0;
+ int save_err;
+ char *cwd;
+ char *cp;
+
+ /* First make sure the parameters are reasonable. */
+ if (dir[0] == '\0')
+ {
+ __set_errno (ENOTDIR);
+ return -1;
+ }
- if (flag == FTW_D)
+ data.maxdir = descriptors < 1 ? 1 : descriptors;
+ data.actdir = 0;
+ data.dirstreams = (struct dir_data **) alloca (data.maxdir
+ * sizeof (struct dir_data *));
+ memset (data.dirstreams, '\0', data.maxdir * sizeof (struct dir_data *));
+
+ data.dirbufsize = MAX (2 * strlen (dir), PATH_MAX);
+ data.dirbuf = (char *) malloc (data.dirbufsize);
+ if (data.dirbuf == NULL)
+ return -1;
+ cp = stpcpy (data.dirbuf, dir);
+ /* Strip trailing slashes. */
+ while (cp > data.dirbuf + 1 && cp[-1] == '/')
+ --cp;
+ *cp = '\0';
+
+ data.ftw.level = 0;
+
+ /* Find basename. */
+ while (cp > data.dirbuf && cp[-1] != '/')
+ --cp;
+ data.ftw.base = cp - data.dirbuf;
+
+ data.flags = flags;
+
+ /* This assignment might seem to be strange but it is what we want.
+ The trick is that the first three arguments to the `ftw' and
+ `nftw' callback functions are equal. Therefore we can call in
+ every case the callback using the format of the `nftw' version
+ and get the correct result since the stack layout for a function
+ call in C allows this. */
+ data.func = (__nftw_func_t) func;
+
+ /* Since we internally use the complete set of FTW_* values we need
+ to reduce the value range before calling a `ftw' callback. */
+ data.cvt_arr = is_nftw ? nftw_arr : ftw_arr;
+
+ /* Now go to the directory containing the initial file/directory. */
+ if ((flags & FTW_CHDIR) && data.ftw.base > 0)
{
- if (retval == 0)
- retval = ftw_dir (dirs, 0, descriptors, buf, len, func);
- if (dirs[0] != NULL)
+ /* GNU extension ahead. */
+ cwd = getcwd (NULL, 0);
+ if (cwd == NULL)
+ result = -1;
+ else
{
- int save;
-
- save = errno;
- closedir (dirs[0]);
- __set_errno (save);
+ /* Change to the directory the file is in. In data.dirbuf
+ we have a writable copy of the file name. Just NUL
+ terminate it for now and change the directory. */
+ if (data.ftw.base == 1)
+ /* I.e., the file is in the root directory. */
+ result = chdir ("/");
+ else
+ {
+ char ch = data.dirbuf[data.ftw.base - 1];
+ data.dirbuf[data.ftw.base - 1] = '\0';
+ result = chdir (data.dirbuf);
+ data.dirbuf[data.ftw.base - 1] = ch;
+ }
}
}
- return retval;
+ /* Get stat info for start directory. */
+ if (result == 0)
+ if (((flags & FTW_PHYS) ? lstat : stat) (data.dirbuf, &data.st) < 0)
+ {
+ if (errno == EACCES)
+ result = (*data.func) (data.dirbuf, &data.st, FTW_NS, &data.ftw);
+ else if (!(flags & FTW_PHYS)
+ && errno == ENOENT
+ && lstat (dir, &data.st) == 0 && S_ISLNK (data.st.st_mode))
+ result = (*data.func) (data.dirbuf, &data.st, data.cvt_arr[FTW_SLN],
+ &data.ftw);
+ else
+ /* No need to call the callback since we cannot say anything
+ about the object. */
+ result = -1;
+ }
+ else
+ {
+ if (S_ISDIR (data.st.st_mode))
+ {
+ data.dev = data.st.st_dev;
+ result = ftw_dir (&data);
+ }
+ else
+ {
+ int flag = S_ISLNK (data.st.st_mode) ? FTW_SL : FTW_F;
+
+ result = (*data.func) (data.dirbuf, &data.st, data.cvt_arr[flag],
+ &data.ftw);
+ }
+ }
+
+ /* Return to the start directory (if necessary). */
+ if (cwd != NULL)
+ {
+ int save_err = errno;
+ chdir (cwd);
+ free (cwd);
+ __set_errno (save_err);
+ }
+
+ /* Free all memory. */
+ save_err = errno;
+ free (data.dirbuf);
+ __set_errno (save_err);
+
+ return result;
+}
+
+
+
+/* Entry points. */
+
+int
+ftw (path, func, descriptors)
+ const char *path;
+ __ftw_func_t func;
+ int descriptors;
+{
+ return ftw_startup (path, 0, func, descriptors, 0);
+}
+
+int
+nftw (path, func, descriptors, flags)
+ const char *path;
+ __nftw_func_t func;
+ int descriptors;
+ int flags;
+{
+ return ftw_startup (path, 1, func, descriptors, flags);
}