libkmod: update remaining function to return the error code

Rework the function signature and return the error code instead of the
stripped module. Thus we no longer explicitly set errno.

v2:
 - kmod_file_open() - use _cleanup_free_, return errno instead of ENOMEM

Reference: https://github.com/kmod-project/kmod/issues/244
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-file.c b/libkmod/libkmod-file.c
index 23057fa6e12e4de46247b332c37ad21a994c146f..d651fa2e4eb5ee49a5b6cd6416225817570d786c 100644 (file)
--- a/libkmod/libkmod-file.c
+++ b/libkmod/libkmod-file.c
@@ -58,57 +58,53 @@ static const struct comp_type {
        // clang-format on
 };
 
-struct kmod_elf *kmod_file_get_elf(struct kmod_file *file)
+int kmod_file_get_elf(struct kmod_file *file, struct kmod_elf **elf)
 {
-       int err;
-
-       if (file->elf)
-               return file->elf;
-
-       err = kmod_file_load_contents(file);
-       if (err) {
-               errno = -err;
-               return NULL;
+       if (!file->elf) {
+               int err = kmod_file_load_contents(file);
+               if (err)
+                       return err;
+
+               err = kmod_elf_new(file->memory, file->size, &file->elf);
+               if (err)
+                       return err;
        }
 
-       err = kmod_elf_new(file->memory, file->size, &file->elf);
-       if (err) {
-               errno = -err;
-               return NULL;
-       }
-       return file->elf;
+       *elf = file->elf;
+       return 0;
 }
 
-struct kmod_file *kmod_file_open(const struct kmod_ctx *ctx, const char *filename)
+int kmod_file_open(const struct kmod_ctx *ctx, const char *filename,
+                  struct kmod_file **out_file)
 {
-       struct kmod_file *file;
+       _cleanup_free_ struct kmod_file *file;
        char buf[7];
        ssize_t sz;
+       int ret;
 
        assert_cc(sizeof(magic_zstd) < sizeof(buf));
        assert_cc(sizeof(magic_xz) < sizeof(buf));
        assert_cc(sizeof(magic_zlib) < sizeof(buf));
 
        file = calloc(1, sizeof(struct kmod_file));
-       if (file == NULL)
-               return NULL;
+       if (file == NULL) {
+               file = NULL;
+               return -ENOMEM;
+       }
 
        file->fd = open(filename, O_RDONLY | O_CLOEXEC);
-       if (file->fd < 0) {
-               free(file);
-               return NULL;
-       }
+       if (file->fd < 0)
+               return -errno;
 
        sz = pread_str_safe(file->fd, buf, sizeof(buf), 0);
        if (sz != (sizeof(buf) - 1)) {
                if (sz < 0)
-                       errno = -sz;
+                       ret = (int)sz;
                else
-                       errno = EINVAL;
+                       ret = -EINVAL;
 
                close(file->fd);
-               free(file);
-               return NULL;
+               return ret;
        }
 
        for (unsigned int i = 0; i < ARRAY_SIZE(comp_types); i++) {
@@ -124,7 +120,9 @@ struct kmod_file *kmod_file_open(const struct kmod_ctx *ctx, const char *filenam
 
        file->ctx = ctx;
 
-       return file;
+       *out_file = file;
+       file = NULL;
+       return 0;
 }
 
 /*

diff --git a/libkmod/libkmod-internal.h b/libkmod/libkmod-internal.h
index 17e6e5f5a2d8c9fadfa6ba62d1494efb4671e60c..c4c24e6f32e69f418c367e31fc5441da47fc15d9 100644 (file)
--- a/libkmod/libkmod-internal.h
+++ b/libkmod/libkmod-internal.h
@@ -135,8 +135,10 @@ _nonnull_(1) void kmod_module_set_required(struct kmod_module *mod, bool require
 _nonnull_all_ bool kmod_module_is_builtin(struct kmod_module *mod);
 
 /* libkmod-file.c */
-_must_check_ _nonnull_all_ struct kmod_file *kmod_file_open(const struct kmod_ctx *ctx, const char *filename);
-_nonnull_all_ struct kmod_elf *kmod_file_get_elf(struct kmod_file *file);
+struct kmod_file;
+struct kmod_elf;
+_must_check_ _nonnull_all_ int kmod_file_open(const struct kmod_ctx *ctx, const char *filename, struct kmod_file **file);
+_must_check_ _nonnull_all_ int kmod_file_get_elf(struct kmod_file *file, struct kmod_elf **elf);
 _nonnull_all_ int kmod_file_load_contents(struct kmod_file *file);
 _must_check_ _nonnull_all_ const void *kmod_file_get_contents(const struct kmod_file *file);
 _must_check_ _nonnull_all_ off_t kmod_file_get_size(const struct kmod_file *file);
@@ -145,7 +147,6 @@ _must_check_ _nonnull_all_ int kmod_file_get_fd(const struct kmod_file *file);
 _nonnull_all_ void kmod_file_unref(struct kmod_file *file);
 
 /* libkmod-elf.c */
-struct kmod_elf;
 struct kmod_modversion {
        uint64_t crc;
        enum kmod_symbol_bind bind;

diff --git a/libkmod/libkmod-module.c b/libkmod/libkmod-module.c
index 5fc40a408b65cff123c19b004393941657ca73bb..796dafa1837292dd4328f351a5bc80a4295439e3 100644 (file)
--- a/libkmod/libkmod-module.c
+++ b/libkmod/libkmod-module.c
@@ -656,11 +656,9 @@ static int do_init_module(struct kmod_module *mod, unsigned int flags, const cha
        int err;
 
        if (flags & (KMOD_INSERT_FORCE_VERMAGIC | KMOD_INSERT_FORCE_MODVERSION)) {
-               elf = kmod_file_get_elf(mod->file);
-               if (elf == NULL) {
-                       err = -errno;
+               err = kmod_file_get_elf(mod->file, &elf);
+               if (err)
                        return err;
-               }
 
                err = kmod_elf_strip(elf, flags, &stripped);
                if (err) {
@@ -702,11 +700,9 @@ KMOD_EXPORT int kmod_module_insert_module(struct kmod_module *mod, unsigned int
        }
 
        if (!mod->file) {
-               mod->file = kmod_file_open(mod->ctx, path);
-               if (mod->file == NULL) {
-                       err = -errno;
+               err = kmod_file_open(mod->ctx, path, &mod->file);
+               if (err)
                        return err;
-               }
        }
 
        err = do_finit_module(mod, flags, args);
@@ -1736,22 +1732,21 @@ KMOD_EXPORT void kmod_module_section_free_list(struct kmod_list *list)
        kmod_list_release(list, kmod_module_section_free);
 }
 
-static struct kmod_elf *kmod_module_get_elf(const struct kmod_module *mod)
+static int kmod_module_get_elf(const struct kmod_module *mod, struct kmod_elf **elf)
 {
        if (mod->file == NULL) {
                const char *path = kmod_module_get_path(mod);
+               int ret;
 
-               if (path == NULL) {
-                       errno = ENOENT;
-                       return NULL;
-               }
+               if (path == NULL)
+                       return -ENOENT;
 
-               ((struct kmod_module *)mod)->file = kmod_file_open(mod->ctx, path);
-               if (mod->file == NULL)
-                       return NULL;
+               ret = kmod_file_open(mod->ctx, path, &((struct kmod_module *)mod)->file);
+               if (ret)
+                       return ret;
        }
 
-       return kmod_file_get_elf(mod->file);
+       return kmod_file_get_elf(mod->file, elf);
 }
 
 struct kmod_module_info {
@@ -1872,9 +1867,9 @@ KMOD_EXPORT int kmod_module_get_info(const struct kmod_module *mod,
                if (count < 0)
                        return count;
        } else {
-               elf = kmod_module_get_elf(mod);
-               if (elf == NULL)
-                       return -errno;
+               ret = kmod_module_get_elf(mod, &elf);
+               if (ret)
+                       return ret;
 
                count = kmod_elf_get_modinfo_strings(elf, &strings);
                if (count < 0)
@@ -2020,9 +2015,9 @@ KMOD_EXPORT int kmod_module_get_versions(const struct kmod_module *mod,
 
        assert(*list == NULL);
 
-       elf = kmod_module_get_elf(mod);
-       if (elf == NULL)
-               return -errno;
+       ret = kmod_module_get_elf(mod, &elf);
+       if (ret)
+               return ret;
 
        count = kmod_elf_get_modversions(elf, &versions);
        if (count < 0)
@@ -2121,9 +2116,9 @@ KMOD_EXPORT int kmod_module_get_symbols(const struct kmod_module *mod,
 
        assert(*list == NULL);
 
-       elf = kmod_module_get_elf(mod);
-       if (elf == NULL)
-               return -errno;
+       ret = kmod_module_get_elf(mod, &elf);
+       if (ret)
+               return ret;
 
        count = kmod_elf_get_symbols(elf, &symbols);
        if (count < 0)
@@ -2227,9 +2222,9 @@ KMOD_EXPORT int kmod_module_get_dependency_symbols(const struct kmod_module *mod
 
        assert(*list == NULL);
 
-       elf = kmod_module_get_elf(mod);
-       if (elf == NULL)
-               return -errno;
+       ret = kmod_module_get_elf(mod, &elf);
+       if (ret)
+               return ret;
 
        count = kmod_elf_get_dependency_symbols(elf, &symbols);
        if (count < 0)