[systemd-devel] [PATCH v2] fsck: Search for fsck.type in PATH

[Mike Gilbert]

Modifies find_binary() to accept NULL in the second argument.

fsck.type lookup logic moved to new fsck_exists() function, with a test.
---
 src/fsck/fsck.c        |  9 ++++-----
 src/shared/generator.c | 11 ++++-------
 src/shared/path-util.c | 11 ++++++++---
 src/shared/util.c      |  8 ++++++++
 src/shared/util.h      |  2 ++
 src/test/test-util.c   | 11 +++++++++++
 6 files changed, 37 insertions(+), 15 deletions(-)

diff --git a/src/fsck/fsck.c b/src/fsck/fsck.c
index 18f2aca..520b1a6 100644
--- a/src/fsck/fsck.c
+++ b/src/fsck/fsck.c
@@ -285,14 +285,13 @@ int main(int argc, char *argv[]) {
 
         type = udev_device_get_property_value(udev_device, "ID_FS_TYPE");
         if (type) {
-                const char *checker = strappenda("/sbin/fsck.", type);
-                r = access(checker, X_OK);
+                r = fsck_exists(type);
                 if (r < 0) {
-                        if (errno == ENOENT) {
-                                log_info("%s doesn't exist, not checking file system.", checker);
+                        if (r == -ENOENT) {
+                                log_info("fsck.%s doesn't exist, not checking file system.", type);
                                 return EXIT_SUCCESS;
                         } else
-                                log_warning("%s cannot be used: %m", checker);
+                                log_warning("fsck.%s cannot be used: %s", type, strerror(-r));
                 }
         }
 
diff --git a/src/shared/generator.c b/src/shared/generator.c
index 6110303..86d30e7 100644
--- a/src/shared/generator.c
+++ b/src/shared/generator.c
@@ -19,6 +19,7 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+#include <string.h>
 #include <unistd.h>
 
 #include "util.h"
@@ -45,16 +46,12 @@ int generator_write_fsck_deps(
         }
 
         if (!isempty(fstype) && !streq(fstype, "auto")) {
-                const char *checker;
                 int r;
-
-                checker = strappenda("/sbin/fsck.", fstype);
-                r = access(checker, X_OK);
+                r = fsck_exists(fstype);
                 if (r < 0) {
-                        log_warning("Checking was requested for %s, but %s cannot be used: %m", what, checker);
-
+                        log_warning("Checking was requested for %s, but fsck.%s cannot be used: %s", what, what, strerror(-r));
                         /* treat missing check as essentially OK */
-                        return errno == ENOENT ? 0 : -errno;
+                        return r == -ENOENT ? 0 : r;
                 }
         }
 
diff --git a/src/shared/path-util.c b/src/shared/path-util.c
index bdc54a9..a530dbe 100644
--- a/src/shared/path-util.c
+++ b/src/shared/path-util.c
@@ -425,7 +425,6 @@ int path_is_os_tree(const char *path) {
 
 int find_binary(const char *name, char **filename) {
         assert(name);
-        assert(filename);
 
         if (strchr(name, '/')) {
                 char *p;
@@ -437,7 +436,10 @@ int find_binary(const char *name, char **filename) {
                 if (!p)
                         return -ENOMEM;
 
-                *filename = p;
+                if (filename)
+                        *filename = p;
+                else
+                        free(p);
                 return 0;
         } else {
                 const char *path;
@@ -464,7 +466,10 @@ int find_binary(const char *name, char **filename) {
                         }
 
                         path_kill_slashes(p);
-                        *filename = p;
+                        if (filename)
+                                *filename = p;
+                        else
+                                free(p);
 
                         return 0;
                 }
diff --git a/src/shared/util.c b/src/shared/util.c
index ffe6624..4cdb561 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -6391,3 +6391,11 @@ void hexdump(FILE *f, const void *p, size_t s) {
                 s -= 16;
         }
 }
+
+int fsck_exists(const char *fstype)
+{
+        const char *checker;
+
+        checker = strappenda("fsck.", fstype);
+        return find_binary(checker, NULL);
+}
diff --git a/src/shared/util.h b/src/shared/util.h
index 90464c9..45a6f26 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -922,3 +922,5 @@ uint64_t physical_memory(void);
 char* mount_test_option(const char *haystack, const char *needle);
 
 void hexdump(FILE *f, const void *p, size_t s);
+
+int fsck_exists(const char *fstype);
diff --git a/src/test/test-util.c b/src/test/test-util.c
index 93929cd..148e54c 100644
--- a/src/test/test-util.c
+++ b/src/test/test-util.c
@@ -675,6 +675,16 @@ static void test_foreach_string(void) {
                 assert_se(streq(x, "zzz"));
 }
 
+static void test_fsck_exists(void) {
+        /* Ensure we use a sane default for PATH. */
+        unsetenv("PATH");
+
+        /* fsck.minix is provided by util-linux and will probably exist. */
+        assert(fsck_exists("minix") == 0);
+
+        assert(fsck_exists("AbCdE") == -ENOENT);
+}
+
 int main(int argc, char *argv[]) {
         log_parse_environment();
         log_open();
@@ -719,6 +729,7 @@ int main(int argc, char *argv[]) {
         test_hexdump();
         test_log2i();
         test_foreach_string();
+        test_fsck_exists();
 
         return 0;
 }
-- 
1.9.2