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
@@ -222,66 +222,67 @@ struct cgit_environment {
 
 struct cgit_context {
         struct cgit_environment env;
         struct cgit_query qry;
         struct cgit_config cfg;
         struct cgit_repo *repo;
         struct cgit_page page;
 };
 
 struct cgit_snapshot_format {
         const char *suffix;
         const char *mimetype;
         write_archive_fn_t write_func;
         int bit;
 };
 
 extern const char *cgit_version;
 
 extern struct cgit_repolist cgit_repolist;
 extern struct cgit_context ctx;
 extern const struct cgit_snapshot_format cgit_snapshot_formats[];
 
 extern struct cgit_repo *cgit_add_repo(const char *url);
 extern struct cgit_repo *cgit_get_repoinfo(const char *url);
 extern void cgit_repo_config_cb(const char *name, const char *value);
 
 extern int chk_zero(int result, char *msg);
 extern int chk_positive(int result, char *msg);
 extern int chk_non_negative(int result, char *msg);
 
 extern char *trim_end(const char *str, char c);
 extern char *strlpart(char *txt, int maxlen);
 extern char *strrpart(char *txt, int maxlen);
 
 extern void cgit_add_ref(struct reflist *list, struct refinfo *ref);
 extern int cgit_refs_cb(const char *refname, const unsigned char *sha1,
                         int flags, void *cb_data);
 
 extern void *cgit_free_commitinfo(struct commitinfo *info);
 
 extern int cgit_diff_files(const unsigned char *old_sha1,
                            const unsigned char *new_sha1,
                            unsigned long *old_size, unsigned long *new_size,
                            int *binary, linediff_fn fn);
 
 extern void cgit_diff_tree(const unsigned char *old_sha1,
                            const unsigned char *new_sha1,
                            filepair_fn fn, const char *prefix);
 
 extern void cgit_diff_commit(struct commit *commit, filepair_fn fn);
 
 extern char *fmt(const char *format,...);
 
 extern struct commitinfo *cgit_parse_commit(struct commit *commit);
 extern struct taginfo *cgit_parse_tag(struct tag *tag);
 extern void cgit_parse_url(const char *url);
 
 extern const char *cgit_repobasename(const char *reponame);
 
 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
@@ -1,137 +1,125 @@
 #include "cgit.h"
 #include "html.h"
 
 #define MAX_PATH 4096
 
 /* return 1 if path contains a objects/ directory and a HEAD file */
 static int is_git_dir(const char *path)
 {
         struct stat st;
         static char buf[MAX_PATH];
 
         if (snprintf(buf, MAX_PATH, "%s/objects", path) >= MAX_PATH) {
                 fprintf(stderr, "Insanely long path: %s\n", path);
                 return 0;
         }
         if (stat(buf, &st)) {
                 if (errno != ENOENT)
                         fprintf(stderr, "Error checking path %s: %s (%d)\n",
                                 path, strerror(errno), errno);
                 return 0;
         }
         if (!S_ISDIR(st.st_mode))
                 return 0;
 
         sprintf(buf, "%s/HEAD", path);
         if (stat(buf, &st)) {
                 if (errno != ENOENT)
                         fprintf(stderr, "Error checking path %s: %s (%d)\n",
                                 path, strerror(errno), errno);
                 return 0;
         }
         if (!S_ISREG(st.st_mode))
                 return 0;
 
         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",
                         path, strerror(errno), errno);
                 return;
         }
         if ((pwd = getpwuid(st.st_uid)) == NULL) {
                 fprintf(stderr, "Error reading owner-info for %s: %s (%d)\n",
                         path, strerror(errno), errno);
                 return;
         }
         if (base == path)
                 p = fmt("%s", path);
         else
                 p = fmt("%s", path + strlen(base) + 1);
 
         if (!strcmp(p + strlen(p) - 5, "/.git"))
                 p[strlen(p) - 5] = '\0';
 
         repo = cgit_add_repo(xstrdup(p));
         repo->name = repo->url;
         repo->path = xstrdup(path);
         repo->owner = (pwd ? xstrdup(pwd->pw_gecos ? pwd->pw_gecos : pwd->pw_name) : "");
 
         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))
                 repo->readme = "README.html";
 }
 
 static void scan_path(const char *base, const char *path)
 {
         DIR *dir;
         struct dirent *ent;
         char *buf;
         struct stat st;
 
         if (is_git_dir(path)) {
                 add_repo(base, path);
                 return;
         }
         dir = opendir(path);
         if (!dir) {
                 fprintf(stderr, "Error opening directory %s: %s (%d)\n",
                         path, strerror(errno), errno);
                 return;
         }
         while((ent = readdir(dir)) != NULL) {
                 if (ent->d_name[0] == '.') {
                         if (ent->d_name[1] == '\0')
                                 continue;
                         if (ent->d_name[1] == '.' && ent->d_name[2] == '\0')
                                 continue;
                 }
                 buf = malloc(strlen(path) + strlen(ent->d_name) + 2);
                 if (!buf) {
                         fprintf(stderr, "Alloc error on %s: %s (%d)\n",
                                 path, strerror(errno), errno);
                         exit(1);
                 }
                 sprintf(buf, "%s/%s", path, ent->d_name);
                 if (stat(buf, &st)) {
                         fprintf(stderr, "Error checking path %s: %s (%d)\n",
                                 buf, strerror(errno), errno);
                         free(buf);
                         continue;
                 }
                 if (S_ISDIR(st.st_mode))
                         scan_path(base, buf);
                 free(buf);
         }
         closedir(dir);
 }
 
 void scan_tree(const char *path)
 {
         scan_path(path, path);
 }
diff --git a/shared.c b/shared.c
index 911a55a..4cb9573 100644
--- a/shared.c
+++ b/shared.c
@@ -332,64 +332,85 @@ void cgit_diff_commit(struct commit *commit, filepair_fn fn)
         cgit_diff_tree(old_sha1, commit->object.sha1, fn, NULL);
 }
 
 int cgit_parse_snapshots_mask(const char *str)
 {
         const struct cgit_snapshot_format *f;
         static const char *delim = " \t,:/|;";
         int tl, sl, rv = 0;
 
         /* favor legacy setting */
         if(atoi(str))
                 return 1;
         for(;;) {
                 str += strspn(str,delim);
                 tl = strcspn(str,delim);
                 if (!tl)
                         break;
                 for (f = cgit_snapshot_formats; f->suffix; f++) {
                         sl = strlen(f->suffix);
                         if((tl == sl && !strncmp(f->suffix, str, tl)) ||
                            (tl == sl-1 && !strncmp(f->suffix+1, str, tl-1))) {
                                 rv |= f->bit;
                                 break;
                         }
                 }
                 str += tl;
         }
         return rv;
 }
 
 int cgit_open_filter(struct cgit_filter *filter)
 {
 
         filter->old_stdout = chk_positive(dup(STDOUT_FILENO),
                 "Unable to duplicate STDOUT");
         chk_zero(pipe(filter->pipe_fh), "Unable to create pipe to subprocess");
         filter->pid = chk_non_negative(fork(), "Unable to create subprocess");
         if (filter->pid == 0) {
                 close(filter->pipe_fh[1]);
                 chk_non_negative(dup2(filter->pipe_fh[0], STDIN_FILENO),
                         "Unable to use pipe as STDIN");
                 execvp(filter->cmd, filter->argv);
                 die("Unable to exec subprocess %s: %s (%d)", filter->cmd,
                         strerror(errno), errno);
         }
         close(filter->pipe_fh[0]);
         chk_non_negative(dup2(filter->pipe_fh[1], STDOUT_FILENO),
                 "Unable to use pipe as STDOUT");
         close(filter->pipe_fh[1]);
         return 0;
 }
 
 int cgit_close_filter(struct cgit_filter *filter)
 {
         chk_non_negative(dup2(filter->old_stdout, STDOUT_FILENO),
                 "Unable to restore STDOUT");
         close(filter->old_stdout);
         if (filter->pid < 0)
                 return 0;
         waitpid(filter->pid, &filter->exitstatus, 0);
         if (WIFEXITED(filter->exitstatus) && !WEXITSTATUS(filter->exitstatus))
                 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
@@ -1,97 +1,98 @@
 /* ui-repolist.c: functions for generating the repolist page
  *
  * Copyright (C) 2006 Lars Hjemli
  *
  * Licensed under GNU General Public License v2
  *   (see COPYING for full license text)
  */
 
 /* This is needed for strcasestr to be defined by <string.h> */
 #define _GNU_SOURCE 1
 #include <string.h>
 
 #include <time.h>
 
 #include "cgit.h"
 #include "html.h"
 #include "ui-shared.h"
 
 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)
 {
         char *path;
         struct stat s;
         struct cgit_repo *r = (struct cgit_repo *)repo;
 
         if (repo->mtime != -1) {
                 *mtime = repo->mtime;
                 return 1;
         }
         path = fmt("%s/%s", repo->path, ctx.cfg.agefile);
         if (stat(path, &s) == 0) {
                 *mtime = read_agefile(path);
                 r->mtime = *mtime;
                 return 1;
         }
 
         path = fmt("%s/refs/heads/%s", repo->path, repo->defbranch);
         if (stat(path, &s) == 0)
                 *mtime = s.st_mtime;
         else
                 *mtime = 0;
 
         r->mtime = *mtime;
         return (r->mtime != 0);
 }
 
 static void print_modtime(struct cgit_repo *repo)
 {
         time_t t;
         if (get_repo_modtime(repo, &t))
                 cgit_print_age(t, -1, NULL);
 }
 
 int is_match(struct cgit_repo *repo)
 {
         if (!ctx.qry.search)
                 return 1;
         if (repo->url && strcasestr(repo->url, ctx.qry.search))
                 return 1;
         if (repo->name && strcasestr(repo->name, ctx.qry.search))
                 return 1;
         if (repo->desc && strcasestr(repo->desc, ctx.qry.search))
                 return 1;
         if (repo->owner && strcasestr(repo->owner, ctx.qry.search))
                 return 1;
         return 0;
 }
 
 int is_in_url(struct cgit_repo *repo)
 {
         if (!ctx.qry.url)
                 return 1;
         if (repo->url && !prefixcmp(repo->url, ctx.qry.url))
                 return 1;
         return 0;
 }
 
 void print_sort_header(const char *title, const char *sort)
 {
         htmlf("<th class='left'><a href='./?s=%s", sort);
         if (ctx.qry.search) {