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[PATCHv2 3/9] archive: refactor list of archive formats

From
Jeff King <peff@peff.net>
Date
Jun 22, 2011, 01:23 UTC
Message-ID
<20110622012333.GC30604@sigill.intra.peff.net>
In-Reply-To
<20110622011923.GA30370@sigill.intra.peff.net>

Most of the tar and zip code was nicely split out into two abstracted files which knew only about their specific formats. The entry point to this code was a single "write archive" function.

However, as these basic formats grow more complex (e.g., by handling multiple file extensions and format names), a static list of the entry point functions won't be enough. Instead, let's provide a way for the tar and zip code to tell the main archive code what they support by registering archiver names and functions.

Signed-off-by: Jeff King <peff@peff.net>
---
New in v2. This turns archivers more into proper objects, rather than a
hard-coded list of functions, and makes the rest of the series much
cleaner.
 archive-tar.c |   16 +++++++++++++---
 archive-zip.c |   13 ++++++++++++-
 archive.c     |   33 +++++++++++++++++----------------
 archive.h     |   17 ++++++++++-------
 4 files changed, 52 insertions(+), 27 deletions(-)
diff --git a/archive-tar.c b/archive-tar.c
index 1ab1a2c..930375b 100644
--- a/archive-tar.c
+++ b/archive-tar.c
@@ -234,12 +234,10 @@ static int git_tar_config(const char *var, const char *value, void *cb)
 	return 0;
 }
 
-int write_tar_archive(struct archiver_args *args)
+static int write_tar_archive(struct archiver_args *args)
 {
 	int err = 0;
 
-	git_config(git_tar_config, NULL);
-
 	if (args->commit_sha1)
 		err = write_global_extended_header(args);
 	if (!err)
@@ -248,3 +246,15 @@ int write_tar_archive(struct archiver_args *args)
 		write_trailer();
 	return err;
 }
+
+static struct archiver tar_archiver = {
+	"tar",
+	write_tar_archive,
+	0
+};
+
+void init_tar_archiver(void)
+{
+	register_archiver(&tar_archiver);
+	git_config(git_tar_config, NULL);
+}
diff --git a/archive-zip.c b/archive-zip.c
index cf28504..a776d83 100644
--- a/archive-zip.c
+++ b/archive-zip.c
@@ -261,7 +261,7 @@ static void dos_time(time_t *time, int *dos_date, int *dos_time)
 	*dos_time = t->tm_sec / 2 + t->tm_min * 32 + t->tm_hour * 2048;
 }
 
-int write_zip_archive(struct archiver_args *args)
+static int write_zip_archive(struct archiver_args *args)
 {
 	int err;
 
@@ -278,3 +278,14 @@ int write_zip_archive(struct archiver_args *args)
 
 	return err;
 }
+
+static struct archiver zip_archiver = {
+	"zip",
+	write_zip_archive,
+	ARCHIVER_WANT_COMPRESSION_LEVELS
+};
+
+void init_zip_archiver(void)
+{
+	register_archiver(&zip_archiver);
+}
diff --git a/archive.c b/archive.c
index 2616676..f0b4e85 100644
--- a/archive.c
+++ b/archive.c
@@ -14,16 +14,15 @@ static char const * const archive_usage[] = {
 	NULL
 };
 
-#define USES_ZLIB_COMPRESSION 1
-
-static const struct archiver {
-	const char *name;
-	write_archive_fn_t write_archive;
-	unsigned int flags;
-} archivers[] = {
-	{ "tar", write_tar_archive },
-	{ "zip", write_zip_archive, USES_ZLIB_COMPRESSION },
-};
+static const struct archiver **archivers;
+static int nr_archivers;
+static int alloc_archivers;
+
+void register_archiver(struct archiver *ar)
+{
+	ALLOC_GROW(archivers, nr_archivers + 1, alloc_archivers);
+	archivers[nr_archivers++] = ar;
+}
 
 static void format_subst(const struct commit *commit,
                          const char *src, size_t len,
@@ -208,9 +207,9 @@ static const struct archiver *lookup_archiver(const char *name)
 	if (!name)
 		return NULL;
 
-	for (i = 0; i < ARRAY_SIZE(archivers); i++) {
-		if (!strcmp(name, archivers[i].name))
-			return &archivers[i];
+	for (i = 0; i < nr_archivers; i++) {
+		if (!strcmp(name, archivers[i]->name))
+			return archivers[i];
 	}
 	return NULL;
 }
@@ -355,8 +354,8 @@ static int parse_archive_args(int argc, const char **argv,
 		base = "";
 
 	if (list) {
-		for (i = 0; i < ARRAY_SIZE(archivers); i++)
-			printf("%s\n", archivers[i].name);
+		for (i = 0; i < nr_archivers; i++)
+			printf("%s\n", archivers[i]->name);
 		exit(0);
 	}
 
@@ -369,7 +368,7 @@ static int parse_archive_args(int argc, const char **argv,
 
 	args->compression_level = Z_DEFAULT_COMPRESSION;
 	if (compression_level != -1) {
-		if ((*ar)->flags & USES_ZLIB_COMPRESSION)
+		if ((*ar)->flags & ARCHIVER_WANT_COMPRESSION_LEVELS)
 			args->compression_level = compression_level;
 		else {
 			die("Argument not supported for format '%s': -%d",
@@ -395,6 +394,8 @@ int write_archive(int argc, const char **argv, const char *prefix,
 		prefix = setup_git_directory_gently(&nongit);
 
 	git_config(git_default_config, NULL);
+	init_tar_archiver();
+	init_zip_archiver();
 
 	argc = parse_archive_args(argc, argv, &ar, &args);
 	if (nongit) {
diff --git a/archive.h b/archive.h
index 038ac35..f39cede 100644
--- a/archive.h
+++ b/archive.h
@@ -14,15 +14,18 @@ struct archiver_args {
 	int compression_level;
 };
 
-typedef int (*write_archive_fn_t)(struct archiver_args *);
+#define ARCHIVER_WANT_COMPRESSION_LEVELS 1
+struct archiver {
+	const char *name;
+	int (*write_archive)(struct archiver_args *);
+	unsigned flags;
+};
+extern void register_archiver(struct archiver *);
 
-typedef int (*write_archive_entry_fn_t)(struct archiver_args *args, const unsigned char *sha1, const char *path, size_t pathlen, unsigned int mode, void *buffer, unsigned long size);
+extern void init_tar_archiver(void);
+extern void init_zip_archiver(void);
 
-/*
- * Archive-format specific backends.
- */
-extern int write_tar_archive(struct archiver_args *);
-extern int write_zip_archive(struct archiver_args *);
+typedef int (*write_archive_entry_fn_t)(struct archiver_args *args, const unsigned char *sha1, const char *path, size_t pathlen, unsigned int mode, void *buffer, unsigned long size);
 
 extern int write_archive_entries(struct archiver_args *args, write_archive_entry_fn_t write_entry);
 extern int write_archive(int argc, const char **argv, const char *prefix, int setup_prefix);

-- 
1.7.5.4.44.g4b107
Previous: Jeff KingNext: Thiago Farina
Message 38 of 56 in “archive: factor out write phase of tar format”
  1. 1/2 archive: factor out write phase of tar formatJeff King, Jun 14, 2011
  2. 2/2 archive: support gzipped tar filesJeff King, Jun 14, 2011
  3. J.H.Jun 14, 2011
  4. Jeff KingJun 14, 2011
  5. René ScharfeJun 14, 2011
  6. Jeff KingJun 14, 2011
  7. Jeff KingJun 14, 2011
  8. 0/7 user-configurable git-archive output formatsJeff King, Jun 15, 2011
  9. 1/7 archive: reorder option parsing and config readingJeff King, Jun 15, 2011
  10. 2/7 archive: add user-configurable tar-filter infrastructureJeff King, Jun 15, 2011
  11. Junio C HamanoJun 15, 2011
  12. Jeff KingJun 16, 2011
  13. 3/7 archive: support user tar-filters via --formatJeff King, Jun 15, 2011
  14. 4/7 archive: advertise user tar-filters in --listJeff King, Jun 15, 2011
  15. 5/7 archive: refactor format-guessing from filenameJeff King, Jun 15, 2011
  16. Junio C HamanoJun 15, 2011
  17. Jeff KingJun 16, 2011
  18. 6/7 archive: match extensions from user-configured formatsJeff King, Jun 15, 2011
  19. 7/7 archive: provide builtin .tar.gz filterJeff King, Jun 15, 2011
  20. Junio C HamanoJun 15, 2011
  21. Junio C HamanoJun 15, 2011
  22. Jeff KingJun 16, 2011
  23. Junio C HamanoJun 16, 2011
  24. Jeff KingJun 16, 2011
  25. Chris WebbJun 16, 2011
  26. Jeff KingJun 16, 2011
  27. Junio C HamanoJun 16, 2011
  28. Jeff KingJun 16, 2011
  29. John SzakmeisterJun 16, 2011
  30. Junio C HamanoJun 16, 2011
  31. Jeff KingJun 16, 2011
  32. René ScharfeJun 18, 2011
  33. Jakub NarebskiJun 18, 2011
  34. Junio C HamanoJun 20, 2011
  35. 0/9 configurable tar compressorsJeff King, Jun 22, 2011
  36. 1/9 archive: reorder option parsing and config readingJeff King, Jun 22, 2011
  37. 2/9 archive-tar: don't reload default config optionsJeff King, Jun 22, 2011
  38. 3/9 archive: refactor list of archive formatsJeff King, Jun 22, 2011
  39. Thiago FarinaJun 23, 2011
  40. Jeff KingJun 23, 2011
  41. 4/9 archive: pass archiver struct to write_archive callbackJeff King, Jun 22, 2011
  42. 5/9 archive: move file extension format-guessing lowerJeff King, Jun 22, 2011
  43. 6/9 archive: refactor file extension format-guessingJeff King, Jun 22, 2011
  44. 7/9 archive: implement configurable tar filtersJeff King, Jun 22, 2011
  45. Jeff KingJun 22, 2011
  46. René ScharfeJun 22, 2011
  47. Jeff KingJun 22, 2011
  48. 8/9 archive: provide builtin .tar.gz filterJeff King, Jun 22, 2011
  49. 9/9 upload-archive: allow user to turn off filtersJeff King, Jun 22, 2011
  50. Jeff KingJun 22, 2011
  51. Jeff KingJun 21, 2011
  52. René ScharfeJun 18, 2011
  53. Junio C HamanoJun 14, 2011
  54. Jeff KingJun 14, 2011
  55. Miles BaderJun 14, 2011
  56. Jeff KingJun 15, 2011

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