examples: create common lg2 executable

Inside of our networking example code, we have a git2 executable
that acts as an entry point to all the different network
examples. As such, it is kind of the same like the normal git(1)
executable in that it simply arbitrates to the respective
subcommands.

Let's extend this approach and merge all examples into a single
standalone lg2 executable. Instead of building an executable
for all the existing examples we have, we now bundle them all
inside of the lg2 one and let them be callable via subcommands.

In the process, we can get rid of duplicated library
initialization, deinitialization and repository discovery code.
Instead of having each subcommand handle these on its own, we
simply do it inside of the single main function now.

Author: pks-t

examples/CMakeLists.txt

@@ -1,25 +1,15 @@
 INCLUDE_DIRECTORIES(${LIBGIT2_INCLUDES})
 INCLUDE_DIRECTORIES(SYSTEM ${LIBGIT2_SYSTEM_INCLUDES})
 
-FILE(GLOB_RECURSE SRC_EXAMPLE_GIT2 network/*.c common.?)
-ADD_EXECUTABLE(cgit2 ${SRC_EXAMPLE_GIT2})
-SET_TARGET_PROPERTIES(cgit2 PROPERTIES C_STANDARD 90)
+FILE(GLOB LG2_SOURCES *.c)
+ADD_EXECUTABLE(lg2 ${LG2_SOURCES})
+SET_TARGET_PROPERTIES(lg2 PROPERTIES C_STANDARD 90)
 
 # Ensure that we do not use deprecated functions internally
 ADD_DEFINITIONS(-DGIT_DEPRECATE_HARD)
 
 IF(WIN32 OR ANDROID)
-	TARGET_LINK_LIBRARIES(cgit2 git2)
+	TARGET_LINK_LIBRARIES(lg2 git2)
 ELSE()
-	TARGET_LINK_LIBRARIES(cgit2 git2 pthread)
+	TARGET_LINK_LIBRARIES(lg2 git2 pthread)
 ENDIF()
-
-FILE(GLOB SRC_EXAMPLE_APPS RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.c)
-FOREACH(src_app ${SRC_EXAMPLE_APPS})
-	STRING(REPLACE ".c" "" app_name ${src_app})
-	IF(NOT ${app_name} STREQUAL "common")
-		ADD_EXECUTABLE(${app_name} ${src_app} "common.c")
-		TARGET_LINK_LIBRARIES(${app_name} git2)
-		SET_TARGET_PROPERTIES(${app_name} PROPERTIES C_STANDARD 90)
-	ENDIF()
-ENDFOREACH()

examples/add.c

@@ -31,22 +31,18 @@ static void parse_opts(int *options, int *count, int argc, char *argv[]);
 void init_array(git_strarray *array, int argc, char **argv);
 int print_matched_cb(const char *path, const char *matched_pathspec, void *payload);
 
-int main (int argc, char** argv)
+int lg2_add(git_repository *repo, int argc, char** argv)
 {
 	git_index_matched_path_cb matched_cb = NULL;
-	git_repository *repo = NULL;
 	git_index *index;
 	git_strarray array = {0};
 	int options = 0, count = 0;
 	struct print_payload payload = {0};
 
-	git_libgit2_init();
-
 	parse_opts(&options, &count, argc, argv);
 
 	init_array(&array, argc-count, argv+count);
 
-	check_lg2(git_repository_open(&repo, "."), "No git repository", NULL);
 	check_lg2(git_repository_index(&index, repo), "Could not open repository index", NULL);
 
 	if (options&VERBOSE || options&SKIP) {
@@ -64,9 +60,6 @@ int main (int argc, char** argv)
 
 	git_index_write(index);
 	git_index_free(index);
-	git_repository_free(repo);
-
-	git_libgit2_shutdown();
 
 	return 0;
 }

examples/blame.c

@@ -35,30 +35,24 @@ struct opts {
 };
 static void parse_opts(struct opts *o, int argc, char *argv[]);
 
-int main(int argc, char *argv[])
+int lg2_blame(git_repository *repo, int argc, char *argv[])
 {
 	int line, break_on_null_hunk;
 	size_t i, rawsize;
 	char spec[1024] = {0};
 	struct opts o = {0};
 	const char *rawdata;
-	git_repository *repo = NULL;
 	git_revspec revspec = {0};
 	git_blame_options blameopts = GIT_BLAME_OPTIONS_INIT;
 	git_blame *blame = NULL;
 	git_blob *blob;
 	git_object *obj;
 
-	git_libgit2_init();
-
 	parse_opts(&o, argc, argv);
 	if (o.M) blameopts.flags |= GIT_BLAME_TRACK_COPIES_SAME_COMMIT_MOVES;
 	if (o.C) blameopts.flags |= GIT_BLAME_TRACK_COPIES_SAME_COMMIT_COPIES;
 	if (o.F) blameopts.flags |= GIT_BLAME_FIRST_PARENT;
 
-	/** Open the repository. */
-	check_lg2(git_repository_open_ext(&repo, ".", 0, NULL), "Couldn't open repository", NULL);
-
 	/**
 	 * The commit range comes in "commitish" form. Use the rev-parse API to
 	 * nail down the end points.
@@ -131,9 +125,6 @@ int main(int argc, char *argv[])
 	/** Cleanup. */
 	git_blob_free(blob);
 	git_blame_free(blame);
-	git_repository_free(repo);
-
-	git_libgit2_shutdown();
 
 	return 0;
 }

examples/cat-file.c

@@ -120,19 +120,14 @@ static void parse_opts(struct opts *o, int argc, char *argv[]);
 
 
 /** Entry point for this command */
-int main(int argc, char *argv[])
+int lg2_cat_file(git_repository *repo, int argc, char *argv[])
 {
-	git_repository *repo;
 	struct opts o = { ".", NULL, 0, 0 };
 	git_object *obj = NULL;
 	char oidstr[GIT_OID_HEXSZ + 1];
 
-	git_libgit2_init();
-
 	parse_opts(&o, argc, argv);
 
-	check_lg2(git_repository_open_ext(&repo, o.dir, 0, NULL),
-			"Could not open repository", NULL);
 	check_lg2(git_revparse_single(&obj, repo, o.rev),
 			"Could not resolve", o.rev);
 
@@ -188,9 +183,6 @@ int main(int argc, char *argv[])
 	}
 
 	git_object_free(obj);
-	git_repository_free(repo);
-
-	git_libgit2_shutdown();
 
 	return 0;
 }

examples/checkout.c

@@ -172,9 +172,8 @@ static int perform_checkout_ref(git_repository *repo, git_annotated_commit *targ
 }
 
 /** That example's entry point */
-int main(int argc, char **argv)
+int lg2_checkout(git_repository *repo, int argc, char **argv)
 {
-	git_repository *repo = NULL;
 	struct args_info args = ARGS_INFO_INIT;
 	checkout_options opts;
 	git_repository_state_t state;
@@ -185,15 +184,6 @@ int main(int argc, char **argv)
 	/** Parse our command line options */
 	parse_options(&path, &opts, &args);
 
-	/** Initialize the library */
-	err = git_libgit2_init();
-	if (!err)
-		check_lg2(err, "Failed to initialize libgit2", NULL);
-
-	/** Open the repository corresponding to the options */
-	check_lg2(git_repository_open_ext(&repo, path, 0, NULL),
-			  "Could not open repository", NULL);
-
 	/** Make sure we're not about to checkout while something else is going on */
 	state = git_repository_state(repo);
 	if (state != GIT_REPOSITORY_STATE_NONE) {
@@ -228,8 +218,5 @@ int main(int argc, char **argv)
 cleanup:
 	git_annotated_commit_free(checkout_target);
 
-	git_repository_free(repo);
-	git_libgit2_shutdown();
-
 	return err;
 }

examples/network/clone.c examples/clone.cexamples/network/clone.c renamed to examples/clone.c

@@ -1,4 +1,4 @@
-#include "../common.h"
+#include "common.h"
 
 typedef struct progress_data {
 	git_transfer_progress fetch_progress;
@@ -63,7 +63,7 @@ static void checkout_progress(const char *path, size_t cur, size_t tot, void *pa
 }
 
 
-int do_clone(git_repository *repo, int argc, char **argv)
+int lg2_clone(git_repository *repo, int argc, char **argv)
 {
 	progress_data pd = {{0}};
 	git_repository *cloned_repo = NULL;

examples/common.h

@@ -26,8 +26,32 @@
 #endif
 #endif
 
+#define ARRAY_SIZE(x) (sizeof(x)/sizeof(*x))
 #define UNUSED(x) (void)(x)
 
+extern int lg2_add(git_repository *repo, int argc, char **argv);
+extern int lg2_blame(git_repository *repo, int argc, char **argv);
+extern int lg2_cat_file(git_repository *repo, int argc, char **argv);
+extern int lg2_checkout(git_repository *repo, int argc, char **argv);
+extern int lg2_clone(git_repository *repo, int argc, char **argv);
+extern int lg2_describe(git_repository *repo, int argc, char **argv);
+extern int lg2_diff(git_repository *repo, int argc, char **argv);
+extern int lg2_fetch(git_repository *repo, int argc, char **argv);
+extern int lg2_for_each_ref(git_repository *repo, int argc, char **argv);
+extern int lg2_general(git_repository *repo, int argc, char **argv);
+extern int lg2_index_pack(git_repository *repo, int argc, char **argv);
+extern int lg2_init(git_repository *repo, int argc, char **argv);
+extern int lg2_log(git_repository *repo, int argc, char **argv);
+extern int lg2_ls_files(git_repository *repo, int argc, char **argv);
+extern int lg2_ls_remote(git_repository *repo, int argc, char **argv);
+extern int lg2_merge(git_repository *repo, int argc, char **argv);
+extern int lg2_remote(git_repository *repo, int argc, char **argv);
+extern int lg2_rev_list(git_repository *repo, int argc, char **argv);
+extern int lg2_rev_parse(git_repository *repo, int argc, char **argv);
+extern int lg2_show_index(git_repository *repo, int argc, char **argv);
+extern int lg2_status(git_repository *repo, int argc, char **argv);
+extern int lg2_tag(git_repository *repo, int argc, char **argv);
+
 /**
  * Check libgit2 error code, printing error to stderr on failure and
  * exiting the program.
@@ -142,8 +166,3 @@ extern int cred_acquire_cb(git_cred **out,
 		const char *username_from_url,
 		unsigned int allowed_types,
 		void *payload);
-
-extern int ls_remote(git_repository *repo, int argc, char **argv);
-extern int fetch(git_repository *repo, int argc, char **argv);
-extern int index_pack(git_repository *repo, int argc, char **argv);
-extern int do_clone(git_repository *repo, int argc, char **argv);

examples/describe.c

@@ -152,23 +152,14 @@ static void describe_options_init(describe_options *opts)
 	git_describe_init_format_options(&opts->format_options, GIT_DESCRIBE_FORMAT_OPTIONS_VERSION);
 }
 
-int main(int argc, char **argv)
+int lg2_describe(git_repository *repo, int argc, char **argv)
 {
-	git_repository *repo;
 	describe_options opts;
 
-	git_libgit2_init();
-
-	check_lg2(git_repository_open_ext(&repo, ".", 0, NULL),
-			"Could not open repository", NULL);
-
 	describe_options_init(&opts);
 	parse_options(&opts, argc, argv);
 
 	do_describe(repo, &opts);
 
-	git_repository_free(repo);
-	git_libgit2_shutdown();
-
 	return 0;
 }

examples/diff.c

@@ -67,23 +67,17 @@ static int color_printer(
 	const git_diff_delta*, const git_diff_hunk*, const git_diff_line*, void*);
 static void diff_print_stats(git_diff *diff, struct opts *o);
 
-int main(int argc, char *argv[])
+int lg2_diff(git_repository *repo, int argc, char *argv[])
 {
-	git_repository *repo = NULL;
 	git_tree *t1 = NULL, *t2 = NULL;
 	git_diff *diff;
 	struct opts o = {
 		GIT_DIFF_OPTIONS_INIT, GIT_DIFF_FIND_OPTIONS_INIT,
 		-1, 0, 0, GIT_DIFF_FORMAT_PATCH, NULL, NULL, "."
 	};
 
-	git_libgit2_init();
-
 	parse_opts(&o, argc, argv);
 
-	check_lg2(git_repository_open_ext(&repo, o.dir, 0, NULL),
-		"Could not open repository", o.dir);
-
 	/**
 	 * Possible argument patterns:
 	 *
@@ -157,13 +151,9 @@ int main(int argc, char *argv[])
 	}
 
 	/** Cleanup before exiting. */
-
 	git_diff_free(diff);
 	git_tree_free(t1);
 	git_tree_free(t2);
-	git_repository_free(repo);
-
-	git_libgit2_shutdown();
 
 	return 0;
 }

examples/network/fetch.c examples/fetch.cexamples/network/fetch.c renamed to examples/fetch.c

@@ -1,4 +1,4 @@
-#include "../common.h"
+#include "common.h"
 
 static int progress_cb(const char *str, int len, void *data)
 {
@@ -54,7 +54,7 @@ static int transfer_progress_cb(const git_transfer_progress *stats, void *payloa
 }
 
 /** Entry point for this command */
-int fetch(git_repository *repo, int argc, char **argv)
+int lg2_fetch(git_repository *repo, int argc, char **argv)
 {
 	git_remote *remote = NULL;
 	const git_transfer_progress *stats;