Fix a warning in using readlink

The use of the same buffer as input and output of readlink
leads to warnings due to restrict use in new versions of
GLIBC

Change-Id: Ifbf1277b88bd18a9df1e18211d4248e94c16d6da
Signed-off-by: José Bollo <jose.bollo@iot.bzh>

diff --git a/src/afb-hook.c b/src/afb-hook.c
index 75e8a69..d9fd1a3 100644 (file)
--- a/src/afb-hook.c
+++ b/src/afb-hook.c
@@ -735,26 +735,26 @@ static void hook_api_event_make_cb(void *closure, const struct afb_hookid *hooki
 
 static void hook_api_rootdir_get_fd_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 {
-       char path[PATH_MAX];
+       char path[PATH_MAX], proc[100];
        if (result < 0)
                _hook_api_(export, "rootdir_get_fd() -> %d, %m", result);
        else {
-               sprintf(path, "/proc/self/fd/%d", result);
-               readlink(path, path, sizeof path);
+               snprintf(proc, sizeof proc, "/proc/self/fd/%d", result);
+               readlink(proc, path, sizeof path);
                _hook_api_(export, "rootdir_get_fd() -> %d = %s", result, path);
        }
 }
 
 static void hook_api_rootdir_open_locale_cb(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *filename, int flags, const char *locale, int result)
 {
-       char path[PATH_MAX];
+       char path[PATH_MAX], proc[100];
        if (!locale)
                locale = "(null)";
        if (result < 0)
                _hook_api_(export, "rootdir_open_locale(%s, %d, %s) -> %d, %m", filename, flags, locale, result);
        else {
-               sprintf(path, "/proc/self/fd/%d", result);
-               readlink(path, path, sizeof path);
+               snprintf(proc, sizeof proc, "/proc/self/fd/%d", result);
+               readlink(proc, path, sizeof path);
                _hook_api_(export, "rootdir_open_locale(%s, %d, %s) -> %d = %s", filename, flags, locale, result, path);
        }
 }

diff --git a/src/afb-trace.c b/src/afb-trace.c
index a603951..5f54b17 100644 (file)
--- a/src/afb-trace.c
+++ b/src/afb-trace.c
@@ -685,33 +685,42 @@ static void hook_api_event_make(void *closure, const struct afb_hookid *hookid,
 
 static void hook_api_rootdir_get_fd(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, int result)
 {
-       char path[PATH_MAX];
+       char path[PATH_MAX], proc[100];
+       const char *key, *val;
 
        if (result >= 0) {
-               sprintf(path, "/proc/self/fd/%d", result);
-               readlink(path, path, sizeof path);
+               snprintf(proc, sizeof proc, "/proc/self/fd/%d", result);
+               readlink(proc, path, sizeof path);
+               key = "path";
+               val = path;
+       } else {
+               key = "error";
+               val = strerror(errno);
        }
 
-       hook_api(closure, hookid, export, "rootdir_get_fd", "{ss}",
-                       result < 0 ? "path" : "error",
-                       result < 0 ? strerror(errno) : path);
+       hook_api(closure, hookid, export, "rootdir_get_fd", "{ss}", key, val);
 }
 
 static void hook_api_rootdir_open_locale(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, const char *filename, int flags, const char *locale, int result)
 {
-       char path[PATH_MAX];
+       char path[PATH_MAX], proc[100];
+       const char *key, *val;
 
        if (result >= 0) {
-               sprintf(path, "/proc/self/fd/%d", result);
-               readlink(path, path, sizeof path);
+               snprintf(proc, sizeof proc, "/proc/self/fd/%d", result);
+               readlink(proc, path, sizeof path);
+               key = "path";
+               val = path;
+       } else {
+               key = "error";
+               val = strerror(errno);
        }
 
        hook_api(closure, hookid, export, "rootdir_open_locale", "{ss si ss* ss}",
                        "file", filename,
                        "flags", flags,
                        "locale", locale,
-                       result < 0 ? "path" : "error",
-                       result < 0 ? strerror(errno) : path);
+                       key, val);
 }
 
 static void hook_api_queue_job(void *closure, const struct afb_hookid *hookid, const struct afb_export *export, void (*callback)(int signum, void *arg), void *argument, void *group, int timeout, int result)