Merge branch 'nd/fopen-errors'

We often try to open a file for reading whose existence is
optional, and silently ignore errors from open/fopen; report such
errors if they are not due to missing files.

* nd/fopen-errors:
  mingw_fopen: report ENOENT for invalid file names
  mingw: verify that paths are not mistaken for remote nicknames
  log: fix memory leak in open_next_file()
  rerere.c: move error_errno() closer to the source system call
  print errno when reporting a system call error
  wrapper.c: make warn_on_inaccessible() static
  wrapper.c: add and use fopen_or_warn()
  wrapper.c: add and use warn_on_fopen_errors()
  config.mak.uname: set FREAD_READS_DIRECTORIES for Darwin, too
  config.mak.uname: set FREAD_READS_DIRECTORIES for Linux and FreeBSD
  clone: use xfopen() instead of fopen()
  use xfopen() in more places
  git_fopen: fix a sparse 'not declared' warning

9 files changed, 17 insertions, 25 deletions

diff --git a/builtin/am.c b/builtin/am.c
index 5ee146bfb..8881d7361 100644
--- a/builtin/am.c
+++ b/builtin/am.c
@@ -1275,12 +1275,8 @@ static int parse_mail(struct am_state *state, const char *mail)
 		die("BUG: invalid value for state->scissors");
 	}
 
-	mi.input = fopen(mail, "r");
-	if (!mi.input)
-		die("could not open input");
-	mi.output = fopen(am_path(state, "info"), "w");
-	if (!mi.output)
-		die("could not open output 'info'");
+	mi.input = xfopen(mail, "r");
+	mi.output = xfopen(am_path(state, "info"), "w");
 	if (mailinfo(&mi, am_path(state, "msg"), am_path(state, "patch")))
 		die("could not parse patch");
 
diff --git a/builtin/blame.c b/builtin/blame.c
index d7a2df3b4..749ad7f05 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -481,7 +481,7 @@ static void output(struct blame_scoreboard *sb, int option)
  */
 static int read_ancestry(const char *graft_file)
 {
-	FILE *fp = fopen(graft_file, "r");
+	FILE *fp = fopen_or_warn(graft_file, "r");
 	struct strbuf buf = STRBUF_INIT;
 	if (!fp)
 		return -1;
diff --git a/builtin/clone.c b/builtin/clone.c
index 743f16ae2..a2ea019c5 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@ -360,7 +360,7 @@ static void copy_alternates(struct strbuf *src, struct strbuf *dst,
 	 * to turn entries with paths relative to the original
 	 * absolute, so that they can be used in the new repository.
 	 */
-	FILE *in = fopen(src->buf, "r");
+	FILE *in = xfopen(src->buf, "r");
 	struct strbuf line = STRBUF_INIT;
 
 	while (strbuf_getline(&line, in) != EOF) {
diff --git a/builtin/commit.c b/builtin/commit.c
index da1ba4c86..ef52457ef 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -1699,10 +1699,7 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
 		if (!reflog_msg)
 			reflog_msg = "commit (merge)";
 		pptr = commit_list_append(current_head, pptr);
-		fp = fopen(git_path_merge_head(), "r");
-		if (fp == NULL)
-			die_errno(_("could not open '%s' for reading"),
-				  git_path_merge_head());
+		fp = xfopen(git_path_merge_head(), "r");
 		while (strbuf_getline_lf(&m, fp) != EOF) {
 			struct commit *parent;
 
diff --git a/builtin/fast-export.c b/builtin/fast-export.c
index 24e29ad7e..2dfed8745 100644
--- a/builtin/fast-export.c
+++ b/builtin/fast-export.c
@@ -907,9 +907,7 @@ static void export_marks(char *file)
 static void import_marks(char *input_file)
 {
 	char line[512];
-	FILE *f = fopen(input_file, "r");
-	if (!f)
-		die_errno("cannot read '%s'", input_file);
+	FILE *f = xfopen(input_file, "r");
 
 	while (fgets(line, sizeof(line), f)) {
 		uint32_t mark;
diff --git a/builtin/fsck.c b/builtin/fsck.c
index cb2ba6cd1..3a2c27f24 100644
--- a/builtin/fsck.c
+++ b/builtin/fsck.c
@@ -280,8 +280,7 @@ static void check_unreachable_object(struct object *obj)
 				free(filename);
 				return;
 			}
-			if (!(f = fopen(filename, "w")))
-				die_errno("Could not open '%s'", filename);
+			f = xfopen(filename, "w");
 			if (obj->type == OBJ_BLOB) {
 				if (stream_blob_to_fd(fileno(f), &obj->oid, NULL, 1))
 					die_errno("Could not write '%s'", filename);
diff --git a/builtin/log.c b/builtin/log.c
index e89ec941c..a33c1a70a 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -846,8 +846,10 @@ static int open_next_file(struct commit *commit, const char *subject,
 	if (output_directory) {
 		strbuf_addstr(&filename, output_directory);
 		if (filename.len >=
-		    PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
+		    PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len) {
+			strbuf_release(&filename);
 			return error(_("name of output directory is too long"));
+		}
 		strbuf_complete(&filename, '/');
 	}
 
@@ -861,8 +863,11 @@ static int open_next_file(struct commit *commit, const char *subject,
 	if (!quiet)
 		printf("%s\n", filename.buf + outdir_offset);
 
-	if ((rev->diffopt.file = fopen(filename.buf, "w")) == NULL)
-		return error(_("Cannot open patch file %s"), filename.buf);
+	if ((rev->diffopt.file = fopen(filename.buf, "w")) == NULL) {
+		error_errno(_("Cannot open patch file %s"), filename.buf);
+		strbuf_release(&filename);
+		return -1;
+	}
 
 	strbuf_release(&filename);
 	return 0;
diff --git a/builtin/merge.c b/builtin/merge.c
index a4a098f40..eab03a026 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -839,9 +839,7 @@ static int suggest_conflicts(void)
 	struct strbuf msgbuf = STRBUF_INIT;
 
 	filename = git_path_merge_msg();
-	fp = fopen(filename, "a");
-	if (!fp)
-		die_errno(_("Could not open '%s' for writing"), filename);
+	fp = xfopen(filename, "a");
 
 	append_conflicts_hint(&msgbuf);
 	fputs(msgbuf.buf, fp);
diff --git a/builtin/pull.c b/builtin/pull.c
index da8b60fc8..69417e4f3 100644
--- a/builtin/pull.c
+++ b/builtin/pull.c
@@ -337,8 +337,7 @@ static void get_merge_heads(struct oid_array *merge_heads)
 	struct strbuf sb = STRBUF_INIT;
 	struct object_id oid;
 
-	if (!(fp = fopen(filename, "r")))
-		die_errno(_("could not open '%s' for reading"), filename);
+	fp = xfopen(filename, "r");
 	while (strbuf_getline_lf(&sb, fp) != EOF) {
 		if (get_oid_hex(sb.buf, &oid))
 			continue;  /* invalid line: does not start with SHA1 */