[PATCH v5 0/5] allow more sources for config values

[PATCH v5 0/5] allow more sources for config values

[Heiko Voigt]

Hi,

I finally got around rerolling this series.

The fourth iteration can be found here[1]. You can also find these patches as a
branch on my github[2].

There is not many changes since the last iteration. I have added some
documentation for the --blob option and now there is no rename of the
do_config_from() function anymore.

Cheers Heiko

[1] http://article.gmane.org/gmane.comp.version-control.git/223964
[2] https://github.com/hvoigt/git/commits/hv/strbuf_config_parsing-series5


Heiko Voigt (5):
  config: factor out config file stack management
  config: drop cf validity check in get_next_char()
  config: make parsing stack struct independent from actual data source
  teach config --blob option to parse config from database
  do not die when error in config parsing of buf occurs

 Documentation/git-config.txt |   7 ++
 builtin/config.c             |  31 ++++++-
 cache.h                      |   6 +-
 config.c                     | 217 +++++++++++++++++++++++++++++++++----------
 t/t1307-config-blob.sh       |  70 ++++++++++++++
 5 files changed, 278 insertions(+), 53 deletions(-)
 create mode 100755 t/t1307-config-blob.sh

-- 
1.8.3.2.773.gcfaae5b

[PATCH v5 1/5] config: factor out config file stack management

[Heiko Voigt]

Because a config callback may start parsing a new file, the
global context regarding the current config file is stored
as a stack. Currently we only need to manage that stack from
git_config_from_file. Let's factor it out to allow new
sources of config data.

Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
---
 config.c | 42 ++++++++++++++++++++++++++++--------------
 1 file changed, 28 insertions(+), 14 deletions(-)

diff --git a/config.c b/config.c
index d04e815..c165c85 100644
--- a/config.c
+++ b/config.c
@@ -906,6 +906,32 @@ int git_default_config(const char *var, const char *value, void *dummy)
 	return 0;
 }
 
+/*
+ * The fields f and name of top need to be initialized before calling
+ * this function.
+ */
+static int do_config_from(struct config_file *top, config_fn_t fn, void *data)
+{
+	int ret;
+
+	/* push config-file parsing state stack */
+	top->prev = cf;
+	top->linenr = 1;
+	top->eof = 0;
+	strbuf_init(&top->value, 1024);
+	strbuf_init(&top->var, 1024);
+	cf = top;
+
+	ret = git_parse_file(fn, data);
+
+	/* pop config-file parsing state stack */
+	strbuf_release(&top->value);
+	strbuf_release(&top->var);
+	cf = top->prev;
+
+	return ret;
+}
+
 int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 {
 	int ret;
@@ -915,22 +941,10 @@ int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 	if (f) {
 		config_file top;
 
-		/* push config-file parsing state stack */
-		top.prev = cf;
 		top.f = f;
 		top.name = filename;
-		top.linenr = 1;
-		top.eof = 0;
-		strbuf_init(&top.value, 1024);
-		strbuf_init(&top.var, 1024);
-		cf = &top;
-
-		ret = git_parse_file(fn, data);
-
-		/* pop config-file parsing state stack */
-		strbuf_release(&top.value);
-		strbuf_release(&top.var);
-		cf = top.prev;
+
+		ret = do_config_from(&top, fn, data);
 
 		fclose(f);
 	}
-- 
1.8.3.2.773.gcfaae5b

[PATCH v5 2/5] config: drop cf validity check in get_next_char()

[Heiko Voigt]

The global variable cf is set with an initialized value in all codepaths before
calling this function.

The complete call graph looks like this:

  git_config_from_file
    -> do_config_from
      -> git_parse_file
        -> get_next_char
        -> get_value
            -> get_next_char
            -> parse_value
                -> get_next_char
        -> get_base_var
            -> get_next_char
            -> get_extended_base_var
                -> get_next_char

The variable is initialized in do_config_from.

Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
---
 config.c | 29 +++++++++++++----------------
 1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/config.c b/config.c
index c165c85..1ec73ad 100644
--- a/config.c
+++ b/config.c
@@ -169,26 +169,23 @@ int git_config_from_parameters(config_fn_t fn, void *data)
 static int get_next_char(void)
 {
 	int c;
-	FILE *f;
+	FILE *f = cf->f;
 
-	c = '\n';
-	if (cf && ((f = cf->f) != NULL)) {
+	c = fgetc(f);
+	if (c == '\r') {
+		/* DOS like systems */
 		c = fgetc(f);
-		if (c == '\r') {
-			/* DOS like systems */
-			c = fgetc(f);
-			if (c != '\n') {
-				ungetc(c, f);
-				c = '\r';
-			}
-		}
-		if (c == '\n')
-			cf->linenr++;
-		if (c == EOF) {
-			cf->eof = 1;
-			c = '\n';
+		if (c != '\n') {
+			ungetc(c, f);
+			c = '\r';
 		}
 	}
+	if (c == '\n')
+		cf->linenr++;
+	if (c == EOF) {
+		cf->eof = 1;
+		c = '\n';
+	}
 	return c;
 }
 
-- 
1.8.3.2.773.gcfaae5b

[PATCH v5 3/5] config: make parsing stack struct independent from actual data source

[Heiko Voigt]

To simplify adding other sources we extract all functions needed for
parsing into a list of callbacks. We implement those callbacks for the
current file parsing. A new source can implement its own set of callbacks.

Instead of storing the concrete FILE pointer for parsing we store a void
pointer. A new source can use this to store its custom data.

Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
---
 config.c | 64 +++++++++++++++++++++++++++++++++++++++++++---------------------
 1 file changed, 43 insertions(+), 21 deletions(-)

diff --git a/config.c b/config.c
index 1ec73ad..71da389 100644
--- a/config.c
+++ b/config.c
@@ -10,20 +10,41 @@
 #include "strbuf.h"
 #include "quote.h"
 
-typedef struct config_file {
-	struct config_file *prev;
-	FILE *f;
+struct config_source {
+	struct config_source *prev;
+	union {
+		FILE *file;
+	} u;
 	const char *name;
 	int linenr;
 	int eof;
 	struct strbuf value;
 	struct strbuf var;
-} config_file;
 
-static config_file *cf;
+	int (*fgetc)(struct config_source *c);
+	int (*ungetc)(int c, struct config_source *conf);
+	long (*ftell)(struct config_source *c);
+};
+
+static struct config_source *cf;
 
 static int zlib_compression_seen;
 
+static int config_file_fgetc(struct config_source *conf)
+{
+	return fgetc(conf->u.file);
+}
+
+static int config_file_ungetc(int c, struct config_source *conf)
+{
+	return ungetc(c, conf->u.file);
+}
+
+static long config_file_ftell(struct config_source *conf)
+{
+	return ftell(conf->u.file);
+}
+
 #define MAX_INCLUDE_DEPTH 10
 static const char include_depth_advice[] =
 "exceeded maximum include depth (%d) while including\n"
@@ -168,15 +189,13 @@ int git_config_from_parameters(config_fn_t fn, void *data)
 
 static int get_next_char(void)
 {
-	int c;
-	FILE *f = cf->f;
+	int c = cf->fgetc(cf);
 
-	c = fgetc(f);
 	if (c == '\r') {
 		/* DOS like systems */
-		c = fgetc(f);
+		c = cf->fgetc(cf);
 		if (c != '\n') {
-			ungetc(c, f);
+			cf->ungetc(c, cf);
 			c = '\r';
 		}
 	}
@@ -336,7 +355,7 @@ static int get_base_var(struct strbuf *name)
 	}
 }
 
-static int git_parse_file(config_fn_t fn, void *data)
+static int git_parse_source(config_fn_t fn, void *data)
 {
 	int comment = 0;
 	int baselen = 0;
@@ -904,10 +923,11 @@ int git_default_config(const char *var, const char *value, void *dummy)
 }
 
 /*
- * The fields f and name of top need to be initialized before calling
+ * All source specific fields in the union, name and the callbacks
+ * fgetc, ungetc, ftell of top need to be initialized before calling
  * this function.
  */
-static int do_config_from(struct config_file *top, config_fn_t fn, void *data)
+static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
 {
 	int ret;
 
@@ -919,7 +939,7 @@ static int do_config_from(struct config_file *top, config_fn_t fn, void *data)
 	strbuf_init(&top->var, 1024);
 	cf = top;
 
-	ret = git_parse_file(fn, data);
+	ret = git_parse_source(fn, data);
 
 	/* pop config-file parsing state stack */
 	strbuf_release(&top->value);
@@ -936,10 +956,13 @@ int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 
 	ret = -1;
 	if (f) {
-		config_file top;
+		struct config_source top;
 
-		top.f = f;
+		top.u.file = f;
 		top.name = filename;
+		top.fgetc = config_file_fgetc;
+		top.ungetc = config_file_ungetc;
+		top.ftell = config_file_ftell;
 
 		ret = do_config_from(&top, fn, data);
 
@@ -1074,7 +1097,6 @@ static int store_aux(const char *key, const char *value, void *cb)
 {
 	const char *ep;
 	size_t section_len;
-	FILE *f = cf->f;
 
 	switch (store.state) {
 	case KEY_SEEN:
@@ -1086,7 +1108,7 @@ static int store_aux(const char *key, const char *value, void *cb)
 				return 1;
 			}
 
-			store.offset[store.seen] = ftell(f);
+			store.offset[store.seen] = cf->ftell(cf);
 			store.seen++;
 		}
 		break;
@@ -1113,19 +1135,19 @@ static int store_aux(const char *key, const char *value, void *cb)
 		 * Do not increment matches: this is no match, but we
 		 * just made sure we are in the desired section.
 		 */
-		store.offset[store.seen] = ftell(f);
+		store.offset[store.seen] = cf->ftell(cf);
 		/* fallthru */
 	case SECTION_END_SEEN:
 	case START:
 		if (matches(key, value)) {
-			store.offset[store.seen] = ftell(f);
+			store.offset[store.seen] = cf->ftell(cf);
 			store.state = KEY_SEEN;
 			store.seen++;
 		} else {
 			if (strrchr(key, '.') - key == store.baselen &&
 			      !strncmp(key, store.key, store.baselen)) {
 					store.state = SECTION_SEEN;
-					store.offset[store.seen] = ftell(f);
+					store.offset[store.seen] = cf->ftell(cf);
 			}
 		}
 	}
-- 
1.8.3.2.773.gcfaae5b

[PATCH v5 4/5] teach config --blob option to parse config from database

[Heiko Voigt]

This can be used to read configuration values directly from git's
database. For example it is useful for reading to be checked out
.gitmodules files directly from the database.

Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
---
 Documentation/git-config.txt |  7 ++++
 builtin/config.c             | 31 +++++++++++++---
 cache.h                      |  6 +++-
 config.c                     | 86 ++++++++++++++++++++++++++++++++++++++++++--
 t/t1307-config-blob.sh       | 70 ++++++++++++++++++++++++++++++++++++
 5 files changed, 193 insertions(+), 7 deletions(-)
 create mode 100755 t/t1307-config-blob.sh

diff --git a/Documentation/git-config.txt b/Documentation/git-config.txt
index fbad05e..5c9ddbe 100644
--- a/Documentation/git-config.txt
+++ b/Documentation/git-config.txt
@@ -127,6 +127,13 @@ See also <<FILES>>.
 --file config-file::
 	Use the given config file instead of the one specified by GIT_CONFIG.
 
+--blob blob::
+	Similar to '--file' but use the given blob instead of a file. E.g.
+	you can use 'master:.gitmodules' to read values from the file
+	'.gitmodules' in the master branch. See "SPECIFYING REVISIONS"
+	section in linkgit:gitrevisions[7] for a more complete list of
+	ways to spell blob names.
+
 --remove-section::
 	Remove the given section from the configuration file.
 
diff --git a/builtin/config.c b/builtin/config.c
index 7759671..4010c43 100644
--- a/builtin/config.c
+++ b/builtin/config.c
@@ -21,6 +21,7 @@ static char term = '\n';
 
 static int use_global_config, use_system_config, use_local_config;
 static const char *given_config_file;
+static const char *given_config_blob;
 static int actions, types;
 static const char *get_color_slot, *get_colorbool_slot;
 static int end_null;
@@ -53,6 +54,7 @@ static struct option builtin_config_options[] = {
 	OPT_BOOLEAN(0, "system", &use_system_config, N_("use system config file")),
 	OPT_BOOLEAN(0, "local", &use_local_config, N_("use repository config file")),
 	OPT_STRING('f', "file", &given_config_file, N_("file"), N_("use given config file")),
+	OPT_STRING(0, "blob", &given_config_blob, N_("blob-id"), N_("read config from given blob object")),
 	OPT_GROUP(N_("Action")),
 	OPT_BIT(0, "get", &actions, N_("get value: name [value-regex]"), ACTION_GET),
 	OPT_BIT(0, "get-all", &actions, N_("get all values: key [value-regex]"), ACTION_GET_ALL),
@@ -218,7 +220,8 @@ static int get_value(const char *key_, const char *regex_)
 	}
 
 	git_config_with_options(collect_config, &values,
-				given_config_file, respect_includes);
+				given_config_file, given_config_blob,
+				respect_includes);
 
 	ret = !values.nr;
 
@@ -302,7 +305,8 @@ static void get_color(const char *def_color)
 	get_color_found = 0;
 	parsed_color[0] = '\0';
 	git_config_with_options(git_get_color_config, NULL,
-				given_config_file, respect_includes);
+				given_config_file, given_config_blob,
+				respect_includes);
 
 	if (!get_color_found && def_color)
 		color_parse(def_color, "command line", parsed_color);
@@ -331,7 +335,8 @@ static int get_colorbool(int print)
 	get_diff_color_found = -1;
 	get_color_ui_found = -1;
 	git_config_with_options(git_get_colorbool_config, NULL,
-				given_config_file, respect_includes);
+				given_config_file, given_config_blob,
+				respect_includes);
 
 	if (get_colorbool_found < 0) {
 		if (!strcmp(get_colorbool_slot, "color.diff"))
@@ -353,6 +358,12 @@ static int get_colorbool(int print)
 		return get_colorbool_found ? 0 : 1;
 }
 
+static void check_blob_write(void)
+{
+	if (given_config_blob)
+		die("writing config blobs is not supported");
+}
+
 int cmd_config(int argc, const char **argv, const char *prefix)
 {
 	int nongit = !startup_info->have_repository;
@@ -364,7 +375,8 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 			     builtin_config_usage,
 			     PARSE_OPT_STOP_AT_NON_OPTION);
 
-	if (use_global_config + use_system_config + use_local_config + !!given_config_file > 1) {
+	if (use_global_config + use_system_config + use_local_config +
+	    !!given_config_file + !!given_config_blob > 1) {
 		error("only one config file at a time.");
 		usage_with_options(builtin_config_usage, builtin_config_options);
 	}
@@ -443,6 +455,7 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 		check_argc(argc, 0, 0);
 		if (git_config_with_options(show_all_config, NULL,
 					    given_config_file,
+					    given_config_blob,
 					    respect_includes) < 0) {
 			if (given_config_file)
 				die_errno("unable to read config file '%s'",
@@ -455,6 +468,8 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 		check_argc(argc, 0, 0);
 		if (!given_config_file && nongit)
 			die("not in a git directory");
+		if (given_config_blob)
+			die("editing blobs is not supported");
 		git_config(git_default_config, NULL);
 		launch_editor(given_config_file ?
 			      given_config_file : git_path("config"),
@@ -462,6 +477,7 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 	}
 	else if (actions == ACTION_SET) {
 		int ret;
+		check_blob_write();
 		check_argc(argc, 2, 2);
 		value = normalize_value(argv[0], argv[1]);
 		ret = git_config_set_in_file(given_config_file, argv[0], value);
@@ -471,18 +487,21 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 		return ret;
 	}
 	else if (actions == ACTION_SET_ALL) {
+		check_blob_write();
 		check_argc(argc, 2, 3);
 		value = normalize_value(argv[0], argv[1]);
 		return git_config_set_multivar_in_file(given_config_file,
 						       argv[0], value, argv[2], 0);
 	}
 	else if (actions == ACTION_ADD) {
+		check_blob_write();
 		check_argc(argc, 2, 2);
 		value = normalize_value(argv[0], argv[1]);
 		return git_config_set_multivar_in_file(given_config_file,
 						       argv[0], value, "^$", 0);
 	}
 	else if (actions == ACTION_REPLACE_ALL) {
+		check_blob_write();
 		check_argc(argc, 2, 3);
 		value = normalize_value(argv[0], argv[1]);
 		return git_config_set_multivar_in_file(given_config_file,
@@ -505,6 +524,7 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 		return get_value(argv[0], argv[1]);
 	}
 	else if (actions == ACTION_UNSET) {
+		check_blob_write();
 		check_argc(argc, 1, 2);
 		if (argc == 2)
 			return git_config_set_multivar_in_file(given_config_file,
@@ -514,12 +534,14 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 						      argv[0], NULL);
 	}
 	else if (actions == ACTION_UNSET_ALL) {
+		check_blob_write();
 		check_argc(argc, 1, 2);
 		return git_config_set_multivar_in_file(given_config_file,
 						       argv[0], NULL, argv[1], 1);
 	}
 	else if (actions == ACTION_RENAME_SECTION) {
 		int ret;
+		check_blob_write();
 		check_argc(argc, 2, 2);
 		ret = git_config_rename_section_in_file(given_config_file,
 							argv[0], argv[1]);
@@ -530,6 +552,7 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 	}
 	else if (actions == ACTION_REMOVE_SECTION) {
 		int ret;
+		check_blob_write();
 		check_argc(argc, 1, 1);
 		ret = git_config_rename_section_in_file(given_config_file,
 							argv[0], NULL);
diff --git a/cache.h b/cache.h
index dd0fb33..99d280a 100644
--- a/cache.h
+++ b/cache.h
@@ -1173,11 +1173,15 @@ extern int update_server_info(int);
 typedef int (*config_fn_t)(const char *, const char *, void *);
 extern int git_default_config(const char *, const char *, void *);
 extern int git_config_from_file(config_fn_t fn, const char *, void *);
+extern int git_config_from_buf(config_fn_t fn, const char *name,
+			       const char *buf, size_t len, void *data);
 extern void git_config_push_parameter(const char *text);
 extern int git_config_from_parameters(config_fn_t fn, void *data);
 extern int git_config(config_fn_t fn, void *);
 extern int git_config_with_options(config_fn_t fn, void *,
-				   const char *filename, int respect_includes);
+				   const char *filename,
+				   const char *blob_ref,
+				   int respect_includes);
 extern int git_config_early(config_fn_t fn, void *, const char *repo_config);
 extern int git_parse_ulong(const char *, unsigned long *);
 extern int git_config_int(const char *, const char *);
diff --git a/config.c b/config.c
index 71da389..75f6ad9 100644
--- a/config.c
+++ b/config.c
@@ -14,6 +14,11 @@ struct config_source {
 	struct config_source *prev;
 	union {
 		FILE *file;
+		struct config_buf {
+			const char *buf;
+			size_t len;
+			size_t pos;
+		} buf;
 	} u;
 	const char *name;
 	int linenr;
@@ -45,6 +50,28 @@ static long config_file_ftell(struct config_source *conf)
 	return ftell(conf->u.file);
 }
 
+
+static int config_buf_fgetc(struct config_source *conf)
+{
+	if (conf->u.buf.pos < conf->u.buf.len)
+		return conf->u.buf.buf[conf->u.buf.pos++];
+
+	return EOF;
+}
+
+static int config_buf_ungetc(int c, struct config_source *conf)
+{
+	if (conf->u.buf.pos > 0)
+		return conf->u.buf.buf[--conf->u.buf.pos];
+
+	return EOF;
+}
+
+static long config_buf_ftell(struct config_source *conf)
+{
+	return conf->u.buf.pos;
+}
+
 #define MAX_INCLUDE_DEPTH 10
 static const char include_depth_advice[] =
 "exceeded maximum include depth (%d) while including\n"
@@ -971,6 +998,57 @@ int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 	return ret;
 }
 
+int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
+			size_t len, void *data)
+{
+	struct config_source top;
+
+	top.u.buf.buf = buf;
+	top.u.buf.len = len;
+	top.u.buf.pos = 0;
+	top.name = name;
+	top.fgetc = config_buf_fgetc;
+	top.ungetc = config_buf_ungetc;
+	top.ftell = config_buf_ftell;
+
+	return do_config_from(&top, fn, data);
+}
+
+static int git_config_from_blob_sha1(config_fn_t fn,
+				     const char *name,
+				     const unsigned char *sha1,
+				     void *data)
+{
+	enum object_type type;
+	char *buf;
+	unsigned long size;
+	int ret;
+
+	buf = read_sha1_file(sha1, &type, &size);
+	if (!buf)
+		return error("unable to load config blob object '%s'", name);
+	if (type != OBJ_BLOB) {
+		free(buf);
+		return error("reference '%s' does not point to a blob", name);
+	}
+
+	ret = git_config_from_buf(fn, name, buf, size, data);
+	free(buf);
+
+	return ret;
+}
+
+static int git_config_from_blob_ref(config_fn_t fn,
+				    const char *name,
+				    void *data)
+{
+	unsigned char sha1[20];
+
+	if (get_sha1(name, sha1) < 0)
+		return error("unable to resolve config blob '%s'", name);
+	return git_config_from_blob_sha1(fn, name, sha1, data);
+}
+
 const char *git_etc_gitconfig(void)
 {
 	static const char *system_wide;
@@ -1036,7 +1114,9 @@ int git_config_early(config_fn_t fn, void *data, const char *repo_config)
 }
 
 int git_config_with_options(config_fn_t fn, void *data,
-			    const char *filename, int respect_includes)
+			    const char *filename,
+			    const char *blob_ref,
+			    int respect_includes)
 {
 	char *repo_config = NULL;
 	int ret;
@@ -1055,6 +1135,8 @@ int git_config_with_options(config_fn_t fn, void *data,
 	 */
 	if (filename)
 		return git_config_from_file(fn, filename, data);
+	else if (blob_ref)
+		return git_config_from_blob_ref(fn, blob_ref, data);
 
 	repo_config = git_pathdup("config");
 	ret = git_config_early(fn, data, repo_config);
@@ -1065,7 +1147,7 @@ int git_config_with_options(config_fn_t fn, void *data,
 
 int git_config(config_fn_t fn, void *data)
 {
-	return git_config_with_options(fn, data, NULL, 1);
+	return git_config_with_options(fn, data, NULL, NULL, 1);
 }
 
 /*
diff --git a/t/t1307-config-blob.sh b/t/t1307-config-blob.sh
new file mode 100755
index 0000000..fdc257e
--- /dev/null
+++ b/t/t1307-config-blob.sh
@@ -0,0 +1,70 @@
+#!/bin/sh
+
+test_description='support for reading config from a blob'
+. ./test-lib.sh
+
+test_expect_success 'create config blob' '
+	cat >config <<-\EOF &&
+	[some]
+		value = 1
+	EOF
+	git add config &&
+	git commit -m foo
+'
+
+test_expect_success 'list config blob contents' '
+	echo some.value=1 >expect &&
+	git config --blob=HEAD:config --list >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'fetch value from blob' '
+	echo true >expect &&
+	git config --blob=HEAD:config --bool some.value >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success 'reading non-existing value from blob is an error' '
+	test_must_fail git config --blob=HEAD:config non.existing
+'
+
+test_expect_success 'reading from blob and file is an error' '
+	test_must_fail git config --blob=HEAD:config --system --list
+'
+
+test_expect_success 'reading from missing ref is an error' '
+	test_must_fail git config --blob=HEAD:doesnotexist --list
+'
+
+test_expect_success 'reading from non-blob is an error' '
+	test_must_fail git config --blob=HEAD --list
+'
+
+test_expect_success 'setting a value in a blob is an error' '
+	test_must_fail git config --blob=HEAD:config some.value foo
+'
+
+test_expect_success 'deleting a value in a blob is an error' '
+	test_must_fail git config --blob=HEAD:config --unset some.value
+'
+
+test_expect_success 'editing a blob is an error' '
+	test_must_fail git config --blob=HEAD:config --edit
+'
+
+test_expect_success 'parse errors in blobs are properly attributed' '
+	cat >config <<-\EOF &&
+	[some]
+		value = "
+	EOF
+	git add config &&
+	git commit -m broken &&
+
+	test_must_fail git config --blob=HEAD:config some.value 2>err &&
+
+	# just grep for our token as the exact error message is likely to
+	# change or be internationalized
+	grep "HEAD:config" err
+'
+
+test_done
-- 
1.8.3.2.773.gcfaae5b

[PATCH v5 5/5] do not die when error in config parsing of buf occurs

[Heiko Voigt]

If a config parsing error in a file occurs we can die and let the user
fix the issue. This is different for the buf parsing function since it
can be used to parse blobs of .gitmodules files. If a parsing error
occurs here we should proceed since otherwise a database containing such
an error in a single revision could be rendered unusable.

Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
---
 config.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/config.c b/config.c
index 75f6ad9..e13a7b6 100644
--- a/config.c
+++ b/config.c
@@ -21,6 +21,7 @@ struct config_source {
 		} buf;
 	} u;
 	const char *name;
+	int die_on_error;
 	int linenr;
 	int eof;
 	struct strbuf value;
@@ -442,7 +443,10 @@ static int git_parse_source(config_fn_t fn, void *data)
 		if (get_value(fn, data, var) < 0)
 			break;
 	}
-	die("bad config file line %d in %s", cf->linenr, cf->name);
+	if (cf->die_on_error)
+		die("bad config file line %d in %s", cf->linenr, cf->name);
+	else
+		return error("bad config file line %d in %s", cf->linenr, cf->name);
 }
 
 static int parse_unit_factor(const char *end, uintmax_t *val)
@@ -950,7 +954,7 @@ int git_default_config(const char *var, const char *value, void *dummy)
 }
 
 /*
- * All source specific fields in the union, name and the callbacks
+ * All source specific fields in the union, die_on_error, name and the callbacks
  * fgetc, ungetc, ftell of top need to be initialized before calling
  * this function.
  */
@@ -987,6 +991,7 @@ int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 
 		top.u.file = f;
 		top.name = filename;
+		top.die_on_error = 1;
 		top.fgetc = config_file_fgetc;
 		top.ungetc = config_file_ungetc;
 		top.ftell = config_file_ftell;
@@ -1007,6 +1012,7 @@ int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
 	top.u.buf.len = len;
 	top.u.buf.pos = 0;
 	top.name = name;
+	top.die_on_error = 0;
 	top.fgetc = config_buf_fgetc;
 	top.ungetc = config_buf_ungetc;
 	top.ftell = config_buf_ftell;
-- 
1.8.3.2.773.gcfaae5b

Re: [PATCH v5 0/5] allow more sources for config values

[Junio C Hamano]

Thanks.

The differences since the last round I see are these.  And I think
the series overall makes sense (I haven't look hard enough to pick
any nits yet, though).

Thanks, will queue.

diff --git a/Documentation/git-config.txt b/Documentation/git-config.txt
index 9ae2508..f0e179e 100644
--- a/Documentation/git-config.txt
+++ b/Documentation/git-config.txt
@@ -118,6 +118,13 @@ See also <<FILES>>.
 --file config-file::
 	Use the given config file instead of the one specified by GIT_CONFIG.
 
+--blob blob::
+	Similar to '--file' but use the given blob instead of a file. E.g.
+	you can use 'master:.gitmodules' to read values from the file
+	'.gitmodules' in the master branch. See "SPECIFYING REVISIONS"
+	section in linkgit:gitrevisions[7] for a more complete list of
+	ways to spell blob names.
+
 --remove-section::
 	Remove the given section from the configuration file.
 
diff --git a/config.c b/config.c
index a8d3dcf..680dd6d 100644
--- a/config.c
+++ b/config.c
@@ -948,7 +948,7 @@ int git_default_config(const char *var, const char *value, void *dummy)
  * fgetc, ungetc, ftell of top need to be initialized before calling
  * this function.
  */
-static int do_config_from_source(struct config_source *top, config_fn_t fn, void *data)
+static int do_config_from(struct config_source *top, config_fn_t fn, void *data)
 {
 	int ret;
 
@@ -986,7 +986,7 @@ int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 		top.ungetc = config_file_ungetc;
 		top.ftell = config_file_ftell;
 
-		ret = do_config_from_source(&top, fn, data);
+		ret = do_config_from(&top, fn, data);
 
 		fclose(f);
 	}
@@ -1007,7 +1007,7 @@ int git_config_from_buf(config_fn_t fn, const char *name, const char *buf,
 	top.ungetc = config_buf_ungetc;
 	top.ftell = config_buf_ftell;
 
-	return do_config_from_source(&top, fn, data);
+	return do_config_from(&top, fn, data);
 }
 
 static int git_config_from_blob_sha1(config_fn_t fn,

Re: [PATCH v5 0/5] allow more sources for config values

[Jeff King]

On Thu, Jul 11, 2013 at 04:26:02PM -0700, Junio C Hamano wrote:

> Thanks.
> 
> The differences since the last round I see are these.  And I think
> the series overall makes sense (I haven't look hard enough to pick
> any nits yet, though).

Both v4 and the interdiff look fine to me. I gave it one more cursory
read-through, and I don't see any problems. So:

Acked-by: Jeff King <peff@peff.net>

-Peff