depmod: Convert depmod_modules_search_path() to strbuf

Replace the scratchbuf usage with corresponding API from strbuf.

depmod_modules_search_path() itself may further be simplified in the
future to share opening the dir with depmod_modules_search_dir(),
but that is left for later.

Signed-off-by: Lucas De Marchi <lucas.de.marchi@gmail.com>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Link: https://github.com/kmod-project/kmod/pull/239

diff --git a/tools/depmod.c b/tools/depmod.c
index a3b75ad8d329d70176fc0baac355234653318283..77bf250cba1a84d66af82268415a0fda6e608f79 100644 (file)
--- a/tools/depmod.c
+++ b/tools/depmod.c
@@ -1345,12 +1345,11 @@ static bool should_exclude_dir(const struct cfg *cfg, const char *name)
        return false;
 }
 
-static int depmod_modules_search_dir(struct depmod *depmod, DIR *d, size_t baselen,
-                                    struct scratchbuf *s_path)
+static int depmod_modules_search_dir(struct depmod *depmod, DIR *d, struct strbuf *path)
 {
        struct dirent *de;
        int err = 0, dfd = dirfd(d);
-       char *path;
+       const size_t baselen = strbuf_used(path);
 
        while ((de = readdir(d)) != NULL) {
                const char *name = de->d_name;
@@ -1360,16 +1359,18 @@ static int depmod_modules_search_dir(struct depmod *depmod, DIR *d, size_t basel
                if (should_exclude_dir(depmod->cfg, name))
                        continue;
 
+               strbuf_shrink_to(path, baselen);
+
                namelen = strlen(name);
-               if (scratchbuf_alloc(s_path, baselen + namelen + 2) < 0) {
+
+               if (!strbuf_pushchars(path, name) ||
+                   /* Ensure space for (possible) '/' or '\0' */
+                   !strbuf_reserve_extra(path, 1)) {
                        err = -ENOMEM;
                        ERR("No memory\n");
                        continue;
                }
 
-               path = scratchbuf_str(s_path);
-               memcpy(path + baselen, name, namelen + 1);
-
                if (de->d_type == DT_REG)
                        is_dir = 0;
                else if (de->d_type == DT_DIR)
@@ -1384,7 +1385,7 @@ static int depmod_modules_search_dir(struct depmod *depmod, DIR *d, size_t basel
                        else if (S_ISDIR(st.st_mode))
                                is_dir = 1;
                        else {
-                               ERR("unsupported file type %s: %o\n", path,
+                               ERR("unsupported file type %s: %o\n", strbuf_str(path),
                                    st.st_mode & S_IFMT);
                                continue;
                        }
@@ -1404,32 +1405,28 @@ static int depmod_modules_search_dir(struct depmod *depmod, DIR *d, size_t basel
                                close(fd);
                                continue;
                        }
-                       path[baselen + namelen] = '/';
-                       path[baselen + namelen + 1] = '\0';
-                       err = depmod_modules_search_dir(depmod, subdir,
-                                                       baselen + namelen + 1, s_path);
+
+                       strbuf_pushchar(path, '/');
+                       err = depmod_modules_search_dir(depmod, subdir, path);
                        closedir(subdir);
                } else {
-                       err = depmod_modules_search_file(depmod, baselen, namelen, path);
+                       err = depmod_modules_search_file(depmod, baselen, namelen,
+                                                        strbuf_str(path));
                }
 
                if (err < 0) {
-                       path[baselen + namelen] = '\0';
-                       ERR("failed %s: %s\n", path, strerror(-err));
+                       ERR("failed %s: %s\n", strbuf_str(path), strerror(-err));
                        err = 0; /* ignore errors */
                }
        }
+
        return err;
 }
 
 static int depmod_modules_search_path(struct depmod *depmod, const char *path)
 {
-       char buf[256];
-       _cleanup_(scratchbuf_release) struct scratchbuf s_path_buf =
-               SCRATCHBUF_INITIALIZER(buf);
-       char *path_buf;
+       DECLARE_STRBUF_WITH_STACK(s_path_buf, 256);
        DIR *d;
-       size_t baselen;
        int err;
 
        d = opendir(path);
@@ -1439,20 +1436,12 @@ static int depmod_modules_search_path(struct depmod *depmod, const char *path)
                return err;
        }
 
-       baselen = strlen(path);
-
-       if (scratchbuf_alloc(&s_path_buf, baselen + 2) < 0) {
+       if (!strbuf_pushchars(&s_path_buf, path) || !strbuf_pushchar(&s_path_buf, '/')) {
                err = -ENOMEM;
                goto out;
        }
-       path_buf = scratchbuf_str(&s_path_buf);
-
-       memcpy(path_buf, path, baselen);
-       path_buf[baselen] = '/';
-       baselen++;
-       path_buf[baselen] = '\0';
 
-       err = depmod_modules_search_dir(depmod, d, baselen, &s_path_buf);
+       err = depmod_modules_search_dir(depmod, d, &s_path_buf);
 out:
        closedir(d);
        return err;