Add and use a common readfile() function

This function is used to read the full content of a textfile into a
newly allocated buffer (with zerotermination).

It replaces the earlier readfile() in scan-tree.c (which was rather
error-prone[1]), and is reused by read_agefile() in ui-repolist.c.

1: No checks for EINTR and EAGAIN, fixed-size buffer

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

4 files changed, 34 insertions, 23 deletions

diff --git a/cgit.h b/cgit.h
index d90ccdc..adb8da4 100644
--- a/cgit.h
+++ b/cgit.h
@@ -283,5 +283,6 @@ extern int cgit_parse_snapshots_mask(const char *str);
 extern int cgit_open_filter(struct cgit_filter *filter);
 extern int cgit_close_filter(struct cgit_filter *filter);
 
+extern int readfile(const char *path, char **buf, size_t *size);
 
 #endif /* CGIT_H */
diff --git a/scan-tree.c b/scan-tree.c
index 47f3988..95dc65b 100644
--- a/scan-tree.c
+++ b/scan-tree.c
@@ -35,25 +35,13 @@ static int is_git_dir(const char *path)
         return 1;
 }
 
-char *readfile(const char *path)
-{
-        FILE *f;
-        static char buf[MAX_PATH];
-
-        if (!(f = fopen(path, "r")))
-                return NULL;
-        buf[0] = 0;
-        fgets(buf, MAX_PATH, f);
-        fclose(f);
-        return buf;
-}
-
 static void add_repo(const char *base, const char *path)
 {
         struct cgit_repo *repo;
         struct stat st;
         struct passwd *pwd;
         char *p;
+        size_t size;
 
         if (stat(path, &st)) {
                 fprintf(stderr, "Error accessing %s: %s (%d)\n",
@@ -80,7 +68,7 @@ static void add_repo(const char *base, const char *path)
 
         p = fmt("%s/description", path);
         if (!stat(p, &st))
-                repo->desc = xstrdup(readfile(p));
+                readfile(p, &repo->desc, &size);
 
         p = fmt("%s/README.html", path);
         if (!stat(p, &st))
diff --git a/shared.c b/shared.c
index 911a55a..4cb9573 100644
--- a/shared.c
+++ b/shared.c
@@ -393,3 +393,24 @@ int cgit_close_filter(struct cgit_filter *filter)
                 return 0;
         die("Subprocess %s exited abnormally", filter->cmd);
 }
+
+/* Read the content of the specified file into a newly allocated buffer,
+ * zeroterminate the buffer and return 0 on success, errno otherwise.
+ */
+int readfile(const char *path, char **buf, size_t *size)
+{
+        int fd;
+        struct stat st;
+
+        fd = open(path, O_RDONLY);
+        if (fd == -1)
+                return errno;
+        if (fstat(fd, &st))
+                return errno;
+        if (!S_ISREG(st.st_mode))
+                return EISDIR;
+        *buf = xmalloc(st.st_size + 1);
+        *size = read_in_full(fd, *buf, st.st_size);
+        (*buf)[*size] = '\0';
+        return (*size == st.st_size ? 0 : errno);
+}
diff --git a/ui-repolist.c b/ui-repolist.c
index 6d2f93f..7c7aa9b 100644
--- a/ui-repolist.c
+++ b/ui-repolist.c
@@ -18,19 +18,20 @@
 
 time_t read_agefile(char *path)
 {
-        FILE *f;
-        static char buf[64], buf2[64];
+        time_t result;
+        size_t size;
+        char *buf;
+        static char buf2[64];
 
-        if (!(f = fopen(path, "r")))
+        if (readfile(path, &buf, &size))
                 return -1;
-        buf[0] = 0;
-        if (fgets(buf, sizeof(buf), f) == NULL)
-                return -1;
-        fclose(f);
+
         if (parse_date(buf, buf2, sizeof(buf2)))
-                return strtoul(buf2, NULL, 10);
+                result = strtoul(buf2, NULL, 10);
         else
-                return 0;
+                result = 0;
+        free(buf);
+        return result;
 }
 
 static int get_repo_modtime(const struct cgit_repo *repo, time_t *mtime)