Add the possibility of giving flags to dir_iterator_begin to initialize
a dir-iterator with special options.
Currently possible flags are:
- DIR_ITERATOR_PEDANTIC, which makes dir_iterator_advance abort
immediately in the case of an error, instead of keep looking for the
next valid entry;
- DIR_ITERATOR_FOLLOW_SYMLINKS, which makes the iterator follow
symlinks and include linked directories' contents in the iteration.
These new flags will be used in a subsequent patch.
Also add tests for the flags' usage and adjust refs/files-backend.c to
the new dir_iterator_begin signature.
Signed-off-by: Matheus Tavares <matheus.bernardino@xxxxxx>
---
dir-iterator.c | 82 +++++++++++++++++++++++++------
dir-iterator.h | 51 ++++++++++++++-----
refs/files-backend.c | 2 +-
t/helper/test-dir-iterator.c | 34 ++++++++++---
t/t0066-dir-iterator.sh | 95 ++++++++++++++++++++++++++++++++++++
5 files changed, 229 insertions(+), 35 deletions(-)
diff --git a/dir-iterator.c b/dir-iterator.c
index 594fe4d67b..52db87bdc9 100644
--- a/dir-iterator.c
+++ b/dir-iterator.c
@@ -6,6 +6,9 @@
struct dir_iterator_level {
DIR *dir;
+ /* The inode number of this level's directory. */
+ ino_t ino;
+
/*
* The length of the directory part of path at this level
* (including a trailing '/'):
@@ -38,13 +41,16 @@ struct dir_iterator_int {
* that will be included in this iteration.
*/
struct dir_iterator_level *levels;
+
+ /* Combination of flags for this dir-iterator */
+ unsigned int flags;
};
/*
* Push a level in the iter stack and initialize it with information from
* the directory pointed by iter->base->path. It is assumed that this
* strbuf points to a valid directory path. Return 0 on success and -1
- * otherwise, leaving the stack unchanged.
+ * otherwise, setting errno accordingly and leaving the stack unchanged.
*/
static int push_level(struct dir_iterator_int *iter)
{
@@ -56,14 +62,17 @@ static int push_level(struct dir_iterator_int *iter)
if (!is_dir_sep(iter->base.path.buf[iter->base.path.len - 1]))
strbuf_addch(&iter->base.path, '/');
level->prefix_len = iter->base.path.len;
+ level->ino = iter->base.st.st_ino;
level->dir = opendir(iter->base.path.buf);
if (!level->dir) {
+ int saved_errno = errno;
if (errno != ENOENT) {
warning_errno("error opening directory '%s'",
iter->base.path.buf);
}
iter->levels_nr--;
+ errno = saved_errno;
return -1;
}
@@ -90,11 +99,13 @@ static int pop_level(struct dir_iterator_int *iter)
/*
* Populate iter->base with the necessary information on the next iteration
* entry, represented by the given dirent de. Return 0 on success and -1
- * otherwise.
+ * otherwise, setting errno accordingly.
*/
static int prepare_next_entry_data(struct dir_iterator_int *iter,
struct dirent *de)
{
+ int err, saved_errno;
+
strbuf_addstr(&iter->base.path, de->d_name);
/*
* We have to reset these because the path strbuf might have
@@ -105,12 +116,34 @@ static int prepare_next_entry_data(struct dir_iterator_int *iter,
iter->base.basename = iter->base.path.buf +
iter->levels[iter->levels_nr - 1].prefix_len;
- if (lstat(iter->base.path.buf, &iter->base.st)) {
- if (errno != ENOENT)
- warning_errno("failed to stat '%s'", iter->base.path.buf);
- return -1;
- }
+ if (iter->flags & DIR_ITERATOR_FOLLOW_SYMLINKS)
+ err = stat(iter->base.path.buf, &iter->base.st);
+ else
+ err = lstat(iter->base.path.buf, &iter->base.st);
+
+ saved_errno = errno;
+ if (err && errno != ENOENT)
+ warning_errno("failed to stat '%s'", iter->base.path.buf);
+
+ errno = saved_errno;
+ return err;
+}
+
+/*
+ * Look for a recursive symlink at iter->base.path pointing to any directory on
+ * the previous stack levels. If it is found, return 1. If not, return 0.
+ */
+static int find_recursive_symlinks(struct dir_iterator_int *iter)
+{
+ int i;
+
+ if (!(iter->flags & DIR_ITERATOR_FOLLOW_SYMLINKS) ||
+ !S_ISDIR(iter->base.st.st_mode))
+ return 0;
+ for (i = 0; i < iter->levels_nr; ++i)
+ if (iter->base.st.st_ino == iter->levels[i].ino)
+ return 1;
return 0;
}
@@ -119,11 +152,11 @@ int dir_iterator_advance(struct dir_iterator *dir_iterator)
struct dir_iterator_int *iter =
(struct dir_iterator_int *)dir_iterator;
- if (S_ISDIR(iter->base.st.st_mode)) {
- if (push_level(iter) && iter->levels_nr == 0) {
- /* Pushing the first level failed */
- return dir_iterator_abort(dir_iterator);
- }
+ if (S_ISDIR(iter->base.st.st_mode) && push_level(iter)) {
+ if (errno != ENOENT && iter->flags & DIR_ITERATOR_PEDANTIC)
+ goto error_out;
+ if (iter->levels_nr == 0)
+ goto error_out;
}
/* Loop until we find an entry that we can give back to the caller. */
@@ -137,22 +170,38 @@ int dir_iterator_advance(struct dir_iterator *dir_iterator)
de = readdir(level->dir);
if (!de) {
- if (errno)
+ if (errno) {
warning_errno("error reading directory '%s'",
iter->base.path.buf);
- else if (pop_level(iter) == 0)
+ if (iter->flags & DIR_ITERATOR_PEDANTIC)
+ goto error_out;
+ } else if (pop_level(iter) == 0) {
return dir_iterator_abort(dir_iterator);
+ }
continue;
}
if (is_dot_or_dotdot(de->d_name))
continue;
- if (prepare_next_entry_data(iter, de))
+ if (prepare_next_entry_data(iter, de)) {
+ if (errno != ENOENT && iter->flags & DIR_ITERATOR_PEDANTIC)
+ goto error_out;
continue;
+ }
+
+ if (find_recursive_symlinks(iter)) {
+ warning("ignoring recursive symlink at '%s'",
+ iter->base.path.buf);
+ continue;
+ }
return ITER_OK;
}
+
+error_out:
+ dir_iterator_abort(dir_iterator);
+ return ITER_ERROR;
}
int dir_iterator_abort(struct dir_iterator *dir_iterator)
@@ -178,7 +227,7 @@ int dir_iterator_abort(struct dir_iterator *dir_iterator)
return ITER_DONE;
}
-struct dir_iterator *dir_iterator_begin(const char *path)
+struct dir_iterator *dir_iterator_begin(const char *path, unsigned int flags)
{
struct dir_iterator_int *iter = xcalloc(1, sizeof(*iter));
struct dir_iterator *dir_iterator = &iter->base;
@@ -189,6 +238,7 @@ struct dir_iterator *dir_iterator_begin(const char *path)
ALLOC_GROW(iter->levels, 10, iter->levels_alloc);
iter->levels_nr = 0;
+ iter->flags = flags;
/*
* Note: stat already checks for NULL or empty strings and
diff --git a/dir-iterator.h b/dir-iterator.h
index 0822821e56..42751091a5 100644
--- a/dir-iterator.h
+++ b/dir-iterator.h
@@ -20,7 +20,8 @@
* A typical iteration looks like this:
*
* int ok;
- * struct iterator *iter = dir_iterator_begin(path);
+ * unsigned int flags = DIR_ITERATOR_PEDANTIC;
+ * struct dir_iterator *iter = dir_iterator_begin(path, flags);
*
* if (!iter)
* goto error_handler;
@@ -44,6 +45,25 @@
* dir_iterator_advance() again.
*/
+/*
+ * Flags for dir_iterator_begin:
+ *
+ * - DIR_ITERATOR_PEDANTIC: override dir-iterator's default behavior
+ * in case of an error at dir_iterator_advance(), which is to keep
+ * looking for a next valid entry. With this flag, resources are freed
+ * and ITER_ERROR is returned immediately. In both cases, a meaningful
+ * warning is emitted. Note: ENOENT errors are always ignored so that
+ * the API users may remove files during iteration.
+ *
+ * - DIR_ITERATOR_FOLLOW_SYMLINKS: make dir-iterator follow symlinks.
+ * i.e., linked directories' contents will be iterated over and
+ * iter->base.st will contain information on the referred files,
+ * not the symlinks themselves, which is the default behavior.
+ * Recursive symlinks are skipped with a warning and broken symlinks
+ * are ignored.
+ */
+#define DIR_ITERATOR_PEDANTIC (1 << 0)
+#define DIR_ITERATOR_FOLLOW_SYMLINKS (1 << 1)
+
struct dir_iterator {
/* The current path: */
struct strbuf path;
@@ -58,29 +78,38 @@ struct dir_iterator {
/* The current basename: */
const char *basename;
- /* The result of calling lstat() on path: */
+ /*
+ * The result of calling lstat() on path; or stat(), if the
+ * DIR_ITERATOR_FOLLOW_SYMLINKS flag was set at
+ * dir_iterator's initialization.
+ */
struct stat st;
};
/*
- * Start a directory iteration over path. On success, return a
- * dir_iterator that holds the internal state of the iteration.
- * In case of failure, return NULL and set errno accordingly.
+ * Start a directory iteration over path with the combination of
+ * options specified by flags. On success, return a dir_iterator
+ * that holds the internal state of the iteration. In case of
+ * failure, return NULL and set errno accordingly.
*
* The iteration includes all paths under path, not including path
* itself and not including "." or ".." entries.
*
- * path is the starting directory. An internal copy will be made.
+ * Parameters are:
+ * - path is the starting directory. An internal copy will be made.
+ * - flags is a combination of the possible flags to initialize a
+ * dir-iterator or 0 for default behavior.
*/
-struct dir_iterator *dir_iterator_begin(const char *path);
+struct dir_iterator *dir_iterator_begin(const char *path, unsigned int flags);
/*
* Advance the iterator to the first or next item and return ITER_OK.
* If the iteration is exhausted, free the dir_iterator and any
- * resources associated with it and return ITER_DONE. On error, free
- * dir_iterator and associated resources and return ITER_ERROR. It is
- * a bug to use iterator or call this function again after it has
- * returned ITER_DONE or ITER_ERROR.
+ * resources associated with it and return ITER_DONE.
+ *
+ * It is a bug to use iterator or call this function again after it
+ * has returned ITER_DONE or ITER_ERROR (which may be returned iff
+ * the DIR_ITERATOR_PEDANTIC flag was set).
*/
int dir_iterator_advance(struct dir_iterator *iterator);
diff --git a/refs/files-backend.c b/refs/files-backend.c
index 7ed81046d4..b1f8f53a09 100644
--- a/refs/files-backend.c
+++ b/refs/files-backend.c
@@ -2150,7 +2150,7 @@ static struct ref_iterator *reflog_iterator_begin(struct ref_store *ref_store,
strbuf_addf(&sb, "%s/logs", gitdir);
- diter = dir_iterator_begin(sb.buf);
+ diter = dir_iterator_begin(sb.buf, 0);
if(!diter)
return empty_ref_iterator_begin();
diff --git a/t/helper/test-dir-iterator.c b/t/helper/test-dir-iterator.c
index fab1ff6237..a5b96cb0dc 100644
--- a/t/helper/test-dir-iterator.c
+++ b/t/helper/test-dir-iterator.c
@@ -4,29 +4,44 @@
#include "iterator.h"
#include "dir-iterator.h"
-/* Argument is a directory path to iterate over */
+/*
+ * usage:
+ * tool-test dir-iterator [--follow-symlinks] [--pedantic] directory_path
+ */
int cmd__dir_iterator(int argc, const char **argv)
{
struct strbuf path = STRBUF_INIT;
struct dir_iterator *diter;
+ unsigned int flags = 0;
+ int iter_status;
+
+ for (++argv, --argc; *argv && starts_with(*argv, "--"); ++argv, --argc) {
+ if (strcmp(*argv, "--follow-symlinks") == 0)
+ flags |= DIR_ITERATOR_FOLLOW_SYMLINKS;
+ else if (strcmp(*argv, "--pedantic") == 0)
+ flags |= DIR_ITERATOR_PEDANTIC;
+ else
+ die("invalid option '%s'", *argv);
+ }
- if (argc < 2)
- die("BUG: test-dir-iterator needs one argument");
-
- strbuf_add(&path, argv[1], strlen(argv[1]));
+ if (!*argv || argc != 1)
+ die("dir-iterator needs exactly one non-option argument");
- diter = dir_iterator_begin(path.buf);
+ strbuf_add(&path, *argv, strlen(*argv));
+ diter = dir_iterator_begin(path.buf, flags);
if (!diter) {
printf("dir_iterator_begin failure: %d\n", errno);
exit(EXIT_FAILURE);
}
- while (dir_iterator_advance(diter) == ITER_OK) {
+ while ((iter_status = dir_iterator_advance(diter)) == ITER_OK) {
if (S_ISDIR(diter->st.st_mode))
printf("[d] ");
else if (S_ISREG(diter->st.st_mode))
printf("[f] ");
+ else if (S_ISLNK(diter->st.st_mode))
+ printf("[s] ");
else
printf("[?] ");
@@ -34,5 +49,10 @@ int cmd__dir_iterator(int argc, const char **argv)
diter->path.buf);
}
+ if (iter_status != ITER_DONE) {
+ printf("dir_iterator_advance failure\n");
+ return 1;
+ }
+
return 0;
}
diff --git a/t/t0066-dir-iterator.sh b/t/t0066-dir-iterator.sh
index c739ed7911..8f996a31fa 100755
--- a/t/t0066-dir-iterator.sh
+++ b/t/t0066-dir-iterator.sh
@@ -65,4 +65,99 @@ test_expect_success 'begin should fail upon non directory paths' '
test_cmp expected-non-dir-output actual-non-dir-output
'
+test_expect_success POSIXPERM,SANITY 'advance should not fail on errors by default' '
+ cat >expected-no-permissions-output <<-EOF &&
+ [d] (a) [a] ./dir3/a
+ EOF
+
+ mkdir -p dir3/a &&
+ > dir3/a/b &&
+ chmod 0 dir3/a &&
+
+ test-tool dir-iterator ./dir3 >actual-no-permissions-output &&
+ test_cmp expected-no-permissions-output actual-no-permissions-output &&
+ chmod 755 dir3/a &&
+ rm -rf dir3
+'
+
+test_expect_success POSIXPERM,SANITY 'advance should fail on errors, w/ pedantic flag' '
+ cat >expected-no-permissions-pedantic-output <<-EOF &&
+ [d] (a) [a] ./dir3/a
+ dir_iterator_advance failure
+ EOF
+
+ mkdir -p dir3/a &&
+ > dir3/a/b &&
+ chmod 0 dir3/a &&
+
+ test_must_fail test-tool dir-iterator --pedantic ./dir3 \
+ >actual-no-permissions-pedantic-output &&
+ test_cmp expected-no-permissions-pedantic-output \
+ actual-no-permissions-pedantic-output &&
+ chmod 755 dir3/a &&
+ rm -rf dir3
+'
+
+test_expect_success SYMLINKS 'setup dirs with symlinks' '
+ mkdir -p dir4/a &&
+ mkdir -p dir4/b/c &&
+ >dir4/a/d &&
+ ln -s d dir4/a/e &&
+ ln -s ../b dir4/a/f &&
+
+ mkdir -p dir5/a/b &&
+ mkdir -p dir5/a/c &&
+ ln -s ../c dir5/a/b/d &&
+ ln -s ../ dir5/a/b/e &&
+ ln -s ../../ dir5/a/b/f
+'
+
+test_expect_success SYMLINKS 'dir-iterator should not follow symlinks by default' '
+ cat >expected-no-follow-sorted-output <<-EOF &&
+ [d] (a) [a] ./dir4/a
+ [d] (b) [b] ./dir4/b
+ [d] (b/c) [c] ./dir4/b/c
+ [f] (a/d) [d] ./dir4/a/d
+ [s] (a/e) [e] ./dir4/a/e
+ [s] (a/f) [f] ./dir4/a/f
+ EOF
+
+ test-tool dir-iterator ./dir4 >out &&
+ sort <out >actual-no-follow-sorted-output &&
+
+ test_cmp expected-no-follow-sorted-output actual-no-follow-sorted-output
+'
+
+test_expect_success SYMLINKS 'dir-iterator should follow symlinks w/ follow flag' '
+ cat >expected-follow-sorted-output <<-EOF &&
+ [d] (a) [a] ./dir4/a
+ [d] (a/f) [f] ./dir4/a/f
+ [d] (a/f/c) [c] ./dir4/a/f/c
+ [d] (b) [b] ./dir4/b
+ [d] (b/c) [c] ./dir4/b/c
+ [f] (a/d) [d] ./dir4/a/d
+ [f] (a/e) [e] ./dir4/a/e
+ EOF
+
+ test-tool dir-iterator --follow-symlinks ./dir4 >out &&
+ sort <out >actual-follow-sorted-output &&
+
+ test_cmp expected-follow-sorted-output actual-follow-sorted-output
+'
+
+
+test_expect_success SYMLINKS 'dir-iterator should ignore recursive symlinks w/ follow flag' '
+ cat >expected-rec-symlinks-sorted-output <<-EOF &&
+ [d] (a) [a] ./dir5/a
+ [d] (a/b) [b] ./dir5/a/b
+ [d] (a/b/d) [d] ./dir5/a/b/d
+ [d] (a/c) [c] ./dir5/a/c
+ EOF
+
+ test-tool dir-iterator --follow-symlinks ./dir5 >out &&
+ sort <out >actual-rec-symlinks-sorted-output &&
+
+ test_cmp expected-rec-symlinks-sorted-output actual-rec-symlinks-sorted-output
+'
+
test_done
--
2.22.0
