From: Emil Velikov <emil.l.velikov@gmail.com>
Date: Wed, 7 May 2025 12:04:25 +0000 (+0100)
Subject: Use %m over strerror(errno) where possible
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fb0e59a12c19a683148cca343e4caec8b2667592;p=thirdparty%2Fkmod.git

Use %m over strerror(errno) where possible

The manual page of strerror() outlines a number of caveats wrt its usage.
Swap for the GNU specific %m printf modifier (also supported on musl and
bionic), which side-steps the issues as much as possible.

Co-authored-by: Cristian Rodríguez <cristian@rodriguez.im>
[emil: split from larger patch, convert more instances to %m]
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Link: https://github.com/kmod-project/kmod/pull/346
Signed-off-by: Lucas De Marchi <lucas.de.marchi@gmail.com>
---

diff --git a/libkmod/libkmod-builtin.c b/libkmod/libkmod-builtin.c
index 2012239a..da5abdc0 100644
--- a/libkmod/libkmod-builtin.c
+++ b/libkmod/libkmod-builtin.c
@@ -90,7 +90,7 @@ static ssize_t get_strings(struct kmod_builtin_info *info, const char *modname,
 		if (n == -1) {
 			if (!feof(info->fp)) {
 				count = -errno;
-				ERR(info->ctx, "get_string: %s\n", strerror(errno));
+				ERR(info->ctx, "get_string: %m\n");
 			}
 			break;
 		}
@@ -182,7 +182,7 @@ ssize_t kmod_builtin_get_modinfo(struct kmod_ctx *ctx, const char *modname,
 		*modinfo = strbuf_to_vector(&buf, (size_t)count);
 		if (*modinfo == NULL) {
 			count = -errno;
-			ERR(ctx, "strbuf_to_vector: %s\n", strerror(errno));
+			ERR(ctx, "strbuf_to_vector: %m\n");
 		}
 	}
 
diff --git a/libkmod/libkmod-module.c b/libkmod/libkmod-module.c
index a9d103e6..3054b9b1 100644
--- a/libkmod/libkmod-module.c
+++ b/libkmod/libkmod-module.c
@@ -334,7 +334,7 @@ KMOD_EXPORT int kmod_module_new_from_path(struct kmod_ctx *ctx, const char *path
 	err = stat(abspath, &st);
 	if (err < 0) {
 		err = -errno;
-		DBG(ctx, "stat %s: %s\n", path, strerror(errno));
+		DBG(ctx, "stat %s: %m\n", path);
 		free(abspath);
 		return err;
 	}
@@ -664,8 +664,7 @@ static int do_init_module(struct kmod_module *mod, unsigned int flags, const cha
 
 		stripped = kmod_elf_strip(elf, flags);
 		if (stripped == NULL) {
-			ERR(mod->ctx, "Failed to strip version information: %s\n",
-			    strerror(errno));
+			ERR(mod->ctx, "Failed to strip version information: %m\n");
 			return -errno;
 		}
 		mem = stripped;
@@ -1362,7 +1361,7 @@ KMOD_EXPORT int kmod_module_new_from_loaded(struct kmod_ctx *ctx, struct kmod_li
 	fp = fopen("/proc/modules", "re");
 	if (fp == NULL) {
 		int err = -errno;
-		ERR(ctx, "could not open /proc/modules: %s\n", strerror(errno));
+		ERR(ctx, "could not open /proc/modules: %m\n");
 		return err;
 	}
 
@@ -1434,7 +1433,7 @@ KMOD_EXPORT int kmod_module_get_initstate(const struct kmod_module *mod)
 	fd = open(path, O_RDONLY | O_CLOEXEC);
 	if (fd < 0) {
 		err = -errno;
-		DBG(mod->ctx, "could not open '%s': %s\n", path, strerror(-err));
+		DBG(mod->ctx, "could not open '%s': %m\n", path);
 
 		if (pathlen > (int)sizeof("/initstate") - 1) {
 			struct stat st;
@@ -1443,7 +1442,7 @@ KMOD_EXPORT int kmod_module_get_initstate(const struct kmod_module *mod)
 				return KMOD_MODULE_COMING;
 
 			err = -errno;
-			DBG(mod->ctx, "could not open '%s': %s\n", path, strerror(-err));
+			DBG(mod->ctx, "could not open '%s': %m\n", path);
 		}
 		return err;
 	}
@@ -1499,7 +1498,7 @@ KMOD_EXPORT long kmod_module_get_size(const struct kmod_module *mod)
 	fp = fopen("/proc/modules", "re");
 	if (fp == NULL) {
 		int err = -errno;
-		ERR(mod->ctx, "could not open /proc/modules: %s\n", strerror(errno));
+		ERR(mod->ctx, "could not open /proc/modules: %m\n");
 		close(dfd);
 		return err;
 	}
@@ -1551,7 +1550,7 @@ KMOD_EXPORT int kmod_module_get_refcnt(const struct kmod_module *mod)
 	fd = open(path, O_RDONLY | O_CLOEXEC);
 	if (fd < 0) {
 		err = -errno;
-		DBG(mod->ctx, "could not open '%s': %s\n", path, strerror(errno));
+		DBG(mod->ctx, "could not open '%s': %m\n", path);
 		return err;
 	}
 
@@ -1580,7 +1579,7 @@ KMOD_EXPORT struct kmod_list *kmod_module_get_holders(const struct kmod_module *
 
 	d = opendir(dname);
 	if (d == NULL) {
-		ERR(mod->ctx, "could not open '%s': %s\n", dname, strerror(errno));
+		ERR(mod->ctx, "could not open '%s': %m\n", dname);
 		return NULL;
 	}
 
@@ -1646,7 +1645,7 @@ KMOD_EXPORT struct kmod_list *kmod_module_get_sections(const struct kmod_module
 
 	d = opendir(dname);
 	if (d == NULL) {
-		ERR(mod->ctx, "could not open '%s': %s\n", dname, strerror(errno));
+		ERR(mod->ctx, "could not open '%s': %m\n", dname);
 		return NULL;
 	}
 
diff --git a/testsuite/delete_module.c b/testsuite/delete_module.c
index 64b5b1cd..68a79220 100644
--- a/testsuite/delete_module.c
+++ b/testsuite/delete_module.c
@@ -137,8 +137,7 @@ static int remove_directory(const char *path)
 
 	dir = opendir(path);
 	if (!dir) {
-		ERR("Failed to open directory %s: %s (errno: %d)\n", path,
-		    strerror(errno), errno);
+		ERR("Failed to open directory %s: %m (errno: %d)\n", path, errno);
 		return -1;
 	}
 
diff --git a/tools/depmod.c b/tools/depmod.c
index cd29bf4f..5f020f83 100644
--- a/tools/depmod.c
+++ b/tools/depmod.c
@@ -3001,7 +3001,7 @@ static int do_depmod(int argc, char *argv[])
 		optind++;
 	} else {
 		if (uname(&un) < 0) {
-			CRIT("uname() failed: %s\n", strerror(errno));
+			CRIT("uname() failed: %m\n");
 			goto cmdline_failed;
 		}
 		cfg.kversion = un.release;