eeshow/: more error returns in file functions; file_open_revision

file_open_revision is for opening files based on the revision history.

eeshow/file.c

@@ -132,18 +132,25 @@ static void *open_vcs(struct file *file)
 			return file->vcs;
 		if (verbose > 1)
 			fprintf(stderr, "could not open %s\n", file->name);
-		return 0;
+		return NULL;
 	}
 }
 
 
-bool file_open(struct file *file, const char *name, const struct file *related)
+static void file_init(struct file *file, const char *name,
+    const struct file *related)
 {
 	file->name = stralloc(name);
 	file->lineno = 0;
 	file->related = related;
 	file->file = NULL;
 	file->vcs = NULL;
+}
+
+
+bool file_open(struct file *file, const char *name, const struct file *related)
+{
+	file_init(file, name, related);
 
 	if (related && related->vcs) {
 		file->vcs = open_vcs(file);
@@ -181,6 +188,22 @@ fail:
 }
 
 
+bool file_open_revision(struct file *file, const char *rev, const char *name,
+    const struct file *related)
+{
+	if (!rev)
+		return file_open(file, name, related);
+
+	file_init(file, name, related);
+	file->vcs = vcs_git_open(rev, name, related ? related->vcs : NULL);
+	if (file->vcs)
+		return 1;
+	if (verbose > 1)
+		fprintf(stderr, "could not open %s at %s\n", name, rev);
+	return 0;
+}
+
+
 bool file_read(struct file *file,
     bool (*parse)(const struct file *file, void *user, const char *line),
     void *user)

eeshow/file.h

@@ -32,6 +32,8 @@ char *file_graft_relative(const char *base, const char *name);
 
 bool file_open(struct file *file, const char *name,
     const struct file *related);
+bool file_open_revision(struct file *file, const char *rev, const char *name,
+    const struct file *related);
 bool file_read(struct file *file,
     bool (*parse)(const struct file *file, void *user, const char *line),
     void *user);

eeshow/git-file.c

@@ -282,12 +282,14 @@ static git_tree_entry *find_file(git_repository *repo, git_tree *tree,
 		fprintf(stderr, "repo dir \"%s\"\n", repo_path);
 
 	canon_path = canonical_path_into_repo(repo_path, path);
+	free(repo_path);
 
 	if (git_tree_entry_bypath(&entry, tree, canon_path)) {
 		const git_error *e = giterr_last();
 
 		fprintf(stderr, "%s: %s\n", path, e->message);
-		exit(1);
+		free(canon_path);
+		return NULL;
 	}
 	free(canon_path);
 
@@ -345,15 +347,18 @@ static bool send_line(const char *s, unsigned len,
 }
 
 
-static void access_file_data(struct vcs_git *vcs_git, const char *name)
+static bool access_file_data(struct vcs_git *vcs_git, const char *name)
 {
 	git_tree_entry *entry;
 
 	entry = find_file(vcs_git->repo, vcs_git->tree, name);
+	if (!entry)
+		return 0;
 	if (verbose)
 		fprintf(stderr, "reading %s\n", name);
 
 	vcs_git->data = get_data(vcs_git->repo, entry, &vcs_git->size);
+	return 1;
 }
 
 
@@ -364,9 +369,7 @@ static bool related_same_repo(struct vcs_git *vcs_git)
 	vcs_git->repo = related->repo;
 	vcs_git->tree = related->tree;
 
-	access_file_data(vcs_git, vcs_git->name);
-
-	return 1;
+	return access_file_data(vcs_git, vcs_git->name);
 }
 
 
@@ -393,7 +396,10 @@ static bool related_only_repo(struct vcs_git *vcs_git)
 	vcs_git->repo = related->repo;
 	vcs_git->tree = related->tree;
 
-	access_file_data(vcs_git, tmp);
+	if (!access_file_data(vcs_git, tmp)) {
+		free(tmp);
+		return 0;
+	}
 
 	free((char *) vcs_git->name);
 	vcs_git->name = tmp;
@@ -439,7 +445,7 @@ struct vcs_git *vcs_git_open(const char *revision, const char *name,
 	vcs_git->repo = select_repo(name);
 	if (!vcs_git->repo) {
 		fprintf(stderr, "%s: not found\n", name);
-		exit(1);
+		goto fail;
 	}
 	if (verbose > 1)
 		fprintf(stderr, "using repository %s\n",
@@ -449,9 +455,14 @@ struct vcs_git *vcs_git_open(const char *revision, const char *name,
 		revision = "HEAD";
 	vcs_git->tree = pick_revision(vcs_git->repo, revision);
 
-	access_file_data(vcs_git, name);
+	if (!access_file_data(vcs_git, name))
+		goto fail;
 
 	return vcs_git;
+
+fail:
+	vcs_git_close(vcs_git);
+	return 0;
 }
 
 

eeshow/git-file.h

@@ -29,6 +29,7 @@
 struct vcs_git;
 struct file;
 
+
 void vcs_git_init(void);
 
 struct vcs_git *vcs_git_open(const char *revision, const char *name,