Add git_repository_init_ext for power initters

The extended version of repository init adds support for many
of the things that you can do with `git init` and sets up
structures that will make it easier to extend further in the
future.

include/git2/repository.h

@@ -83,6 +83,15 @@ GIT_EXTERN(int) git_repository_discover(
 		int across_fs,
 		const char *ceiling_dirs);
 
+/**
+ * Option flags for `git_repository_open_ext`.
+ *
+ * * GIT_REPOSITORY_OPEN_NO_SEARCH - Only open the repository if it can be
+ *   immediately found in the start_path.  Do not walk up from the
+ *   start_path looking at parent directories.
+ * * GIT_REPOSITORY_OPEN_CROSS_FS - Do not continue search across
+ *   filesystem boundaries (as reported by the `stat` system call).
+ */
 enum {
 	GIT_REPOSITORY_OPEN_NO_SEARCH = (1 << 0),
 	GIT_REPOSITORY_OPEN_CROSS_FS  = (1 << 1),
@@ -90,6 +99,20 @@ enum {
 
 /**
  * Find and open a repository with extended controls.
+ *
+ * @param repo_out Pointer to the repo which will be opened.  This can
+ *        actually be NULL if you only want to use the error code to
+ *        see if a repo at this path could be opened.
+ * @param start_path Path to open as git repository.  If the flags
+ *        permit "searching", then this can be a path to a subdirectory
+ *        inside the working directory of the repository.
+ * @param flags A combination of the GIT_REPOSITORY_OPEN flags above.
+ * @param ceiling_dirs A GIT_PATH_LIST_SEPARATOR delimited list of path
+ *        prefixes at which the search for a containing repository should
+ *        terminate.
+ * @return 0 on success, GIT_ENOTFOUND if no repository could be found,
+ *        or -1 if there was a repository but open failed for some reason
+ *        (such as repo corruption or system errors).
  */
 GIT_EXTERN(int) git_repository_open_ext(
 	git_repository **repo,
@@ -118,13 +141,117 @@ GIT_EXTERN(void) git_repository_free(git_repository *repo);
  *
  * @param repo_out pointer to the repo which will be created or reinitialized
  * @param path the path to the repository
- * @param is_bare if true, a Git repository without a working directory is created
- *		at the pointed path. If false, provided path will be considered as the working
- *		directory into which the .git directory will be created.
+ * @param is_bare if true, a Git repository without a working directory is
+ *		created at the pointed path. If false, provided path will be
+ *		considered as the working directory into which the .git directory
+ *		will be created.
  *
  * @return 0 or an error code
  */
-GIT_EXTERN(int) git_repository_init(git_repository **repo_out, const char *path, unsigned is_bare);
+GIT_EXTERN(int) git_repository_init(
+	git_repository **repo_out,
+	const char *path,
+	unsigned is_bare);
+
+/**
+ * Option flags for `git_repository_init_ext`.
+ *
+ * These flags configure extra behaviors to `git_repository_init_ext`.
+ * In every case, the default behavior is the zero value (i.e. flag is
+ * not set).  Just OR the flag values together for the `flags` parameter
+ * when initializing a new repo.  Details of individual values are:
+ *
+ * * BARE   - Create a bare repository with no working directory.
+ * * NO_REINIT - Return an EEXISTS error if the repo_path appears to
+ *        already be an git repository.
+ * * NO_DOTGIT_DIR - Normally a "/.git/" will be appended to the repo
+ *        path for non-bare repos (if it is not already there), but
+ *        passing this flag prevents that behavior.
+ * * MKDIR  - Make the repo_path (and workdir_path) as needed.  Init is
+ *        always willing to create the ".git" directory even without this
+ *        flag.  This flag tells init to create the trailing component of
+ *        the repo and workdir paths as needed.
+ * * MKPATH - Recursively make all components of the repo and workdir
+ *        paths as necessary.
+ * * EXTERNAL_TEMPLATE - libgit2 normally uses internal templates to
+ *        initialize a new repo.  This flags enables external templates,
+ *        looking the "template_path" from the options if set, or the
+ *        `init.templatedir` global config if not, or falling back on
+ *        "/usr/share/git-core/templates" if it exists.
+ * * SHARED_UMASK - Use permissions reported by umask - this is default
+ * * SHARED_GROUP - Use "--shared=group" behavior, chmod'ing the new repo
+ *        to be group writable and "g+sx" for sticky group assignment.
+ * * SHARED_ALL - Use "--shared=all" behavior, adding world readability.
+ * * SHARED_CUSTOM - Use the `mode` value from the init options struct.
+ */
+enum {
+	GIT_REPOSITORY_INIT_BARE              = (1u << 0),
+	GIT_REPOSITORY_INIT_NO_REINIT         = (1u << 1),
+	GIT_REPOSITORY_INIT_NO_DOTGIT_DIR     = (1u << 2),
+	GIT_REPOSITORY_INIT_MKDIR             = (1u << 3),
+	GIT_REPOSITORY_INIT_MKPATH            = (1u << 4),
+	GIT_REPOSITORY_INIT_EXTERNAL_TEMPLATE = (1u << 5),
+	GIT_REPOSITORY_INIT_SHARED_UMASK      = (0u << 6),
+	GIT_REPOSITORY_INIT_SHARED_GROUP      = (1u << 6),
+	GIT_REPOSITORY_INIT_SHARED_ALL        = (2u << 6),
+	GIT_REPOSITORY_INIT_SHARED_CUSTOM     = (3u << 6),
+};
+
+/**
+ * Extended options structure for `git_repository_init_ext`.
+ *
+ * This contains extra options for `git_repository_init_ext` that enable
+ * additional initialization features.  The fields are:
+ *
+ * * flags - Combination of GIT_REPOSITORY_INIT flags above.
+ * * mode  - When GIT_REPOSITORY_INIT_SHARED_CUSTOM is set, this contains
+ *        the mode bits that should be used for directories in the repo.
+ * * workdir_path - The path to the working dir or NULL for default (i.e.
+ *        repo_path parent on non-bare repos).  If a relative path, this
+ *        will be evaluated relative to the repo_path.  If this is not the
+ *        "natural" working directory, a .git gitlink file will be created
+ *        here linking to the repo_path.
+ * * description - If set, this will be used to initialize the "description"
+ *        file in the repository, instead of using the template content.
+ * * template_path - When GIT_REPOSITORY_INIT_EXTERNAL_TEMPLATE is set,
+ *        this contains the path to use for the template directory.  If
+ *        this is NULL, the config or default directory options will be
+ *        used instead.
+ * * initial_head - The name of the head to point HEAD at.  If NULL, then
+ *        this will be treated as "master" and the HEAD ref will be set
+ *        to "refs/heads/master".  If this begins with "refs/" it will be
+ *        used verbatim; otherwise "refs/heads/" will be prefixed.
+ * * origin_url - If this is non-NULL, then after the rest of the
+ *        repository initialization is completed, an "origin" remote
+ *        will be added pointing to this URL.
+ */
+typedef struct {
+	uint32_t    flags;
+	uint32_t    mode;
+	const char *workdir_path;
+	const char *description;
+	const char *template_path;
+	const char *initial_head;
+	const char *origin_url;
+} git_repository_init_options;
+
+/**
+ * Create a new Git repository in the given folder with extended controls.
+ *
+ * This will initialize a new git repository (creating the repo_path
+ * if requested by flags) and working directory as needed.  It will
+ * auto-detect the case sensitivity of the file system and if the
+ * file system supports file mode bits correctly.
+ *
+ * @param repo_out Pointer to the repo which will be created or reinitialized.
+ * @param repo_path The path to the repository.
+ * @param opts Pointer to git_repository_init_options struct.
+ * @return 0 or an error code on failure.
+ */
+GIT_EXTERN(int) git_repository_init_ext(
+	git_repository **repo_out,
+	const char *repo_path,
+	git_repository_init_options *opts);
 
 /**
  * Retrieve and resolve the reference pointed at by HEAD.

src/fileops.c

@@ -239,6 +239,16 @@ void git_futils_mmap_free(git_map *out)
 	p_munmap(out);
 }
 
+int git_futils_mkdir_q(const char *path, const mode_t mode)
+{
+	if (p_mkdir(path, mode) < 0 && errno != EEXIST) {
+		giterr_set(GITERR_OS, "Failed to create directory at '%s'", path);
+		return -1;
+	}
+
+	return 0;
+}
+
 int git_futils_mkdir_r(const char *path, const char *base, const mode_t mode)
 {
 	git_buf make_path = GIT_BUF_INIT;

src/fileops.h

@@ -48,6 +48,11 @@ extern int git_futils_creat_locked(const char *path, const mode_t mode);
 extern int git_futils_creat_locked_withpath(const char *path, const mode_t dirmode, const mode_t mode);
 
 /**
+ * Create a directory if it does not exist
+ */
+extern int git_futils_mkdir_q(const char *path, const mode_t mode);
+
+/**
  * Create a path recursively
  *
  * If a base parameter is being passed, it's expected to be valued with a path pointing to an already

src/repo_template.h

+/*
+ * Copyright (C) 2012 the libgit2 contributors
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_repo_template_h__
+#define INCLUDE_repo_template_h__
+
+#define GIT_OBJECTS_INFO_DIR GIT_OBJECTS_DIR "info/"
+#define GIT_OBJECTS_PACK_DIR GIT_OBJECTS_DIR "pack/"
+
+#define GIT_HOOKS_DIR "hooks/"
+#define GIT_HOOKS_DIR_MODE 0755
+
+#define GIT_HOOKS_README_FILE GIT_HOOKS_DIR "README.sample"
+#define GIT_HOOKS_README_MODE 0755
+#define GIT_HOOKS_README_CONTENT \
+"#!/bin/sh\n"\
+"#\n"\
+"# Place appropriately named executable hook scripts into this directory\n"\
+"# to intercept various actions that git takes.  See `git help hooks` for\n"\
+"# more information.\n"
+
+#define GIT_INFO_DIR "info/"
+#define GIT_INFO_DIR_MODE 0755
+
+#define GIT_INFO_EXCLUDE_FILE GIT_INFO_DIR "exclude"
+#define GIT_INFO_EXCLUDE_MODE 0644
+#define GIT_INFO_EXCLUDE_CONTENT \
+"# File patterns to ignore; see `git help ignore` for more information.\n"\
+"# Lines that start with '#' are comments.\n"
+
+#define GIT_DESC_FILE "description"
+#define GIT_DESC_MODE 0644
+#define GIT_DESC_CONTENT \
+"Unnamed repository; edit this file 'description' to name the repository.\n"
+
+typedef struct {
+	const char *path;
+	mode_t mode;
+	const char *content;
+} repo_template_item;
+
+static repo_template_item repo_template[] = {
+	{ GIT_OBJECTS_INFO_DIR, GIT_OBJECT_DIR_MODE, NULL }, /* '/objects/info/' */
+	{ GIT_OBJECTS_PACK_DIR, GIT_OBJECT_DIR_MODE, NULL }, /* '/objects/pack/' */
+	{ GIT_REFS_HEADS_DIR, GIT_REFS_DIR_MODE, NULL },     /* '/refs/heads/' */
+	{ GIT_REFS_TAGS_DIR, GIT_REFS_DIR_MODE, NULL },      /* '/refs/tags/' */
+	{ GIT_HOOKS_DIR, GIT_HOOKS_DIR_MODE, NULL },         /* '/hooks/' */
+	{ GIT_INFO_DIR, GIT_INFO_DIR_MODE, NULL },           /* '/info/' */
+	{ GIT_DESC_FILE, GIT_DESC_MODE, GIT_DESC_CONTENT },
+	{ GIT_HOOKS_README_FILE, GIT_HOOKS_README_MODE, GIT_HOOKS_README_CONTENT },
+	{ GIT_INFO_EXCLUDE_FILE, GIT_INFO_EXCLUDE_MODE, GIT_INFO_EXCLUDE_CONTENT },
+	{ NULL, 0, NULL }
+};
+
+#endif

src/repository.h

@@ -68,6 +68,14 @@ typedef enum {
 	GIT_EOL_DEFAULT = GIT_EOL_NATIVE
 } git_cvar_value;
 
+/* internal repository init flags */
+enum {
+	GIT_REPOSITORY_INIT__HAS_DOTGIT = (1u << 16),
+	GIT_REPOSITORY_INIT__NATURAL_WD = (1u << 17),
+	GIT_REPOSITORY_INIT__IS_REINIT  = (1u << 18),
+};
+
+
 /** Base git object for inheritance */
 struct git_object {
 	git_cached_obj cached;
@@ -75,6 +83,7 @@ struct git_object {
 	git_otype type;
 };
 
+/** Internal structure for repository object */
 struct git_repository {
 	git_odb *_odb;
 	git_config *_config;
@@ -94,8 +103,7 @@ struct git_repository {
 	git_cvar_value cvar_cache[GIT_CVAR_CACHE_MAX];
 };
 
-/* fully free the object; internal method, do not
- * export */
+/* fully free the object; internal method, DO NOT EXPORT */
 void git_object__free(void *object);
 
 GIT_INLINE(int) git_object__dup(git_object **dest, git_object *source)