* <http://creativecommons.org/publicdomain/zero/1.0/>.
*/
-// [**libgit2**][lg] is a portable, pure C implementation of the Git core
-// methods provided as a re-entrant linkable library with a solid API,
-// allowing you to write native speed custom Git applications in any
-// language which supports C bindings.
-//
-// This file is an example of using that API in a real, compilable C file.
-// As the API is updated, this file will be updated to demonstrate the new
-// functionality.
-//
-// If you're trying to write something in C using [libgit2][lg], you should
-// also check out the generated [API documentation][ap]. We try to link to
-// the relevant sections of the API docs in each section in this file.
-//
-// **libgit2** (for the most part) only implements the core plumbing
-// functions, not really the higher level porcelain stuff. For a primer on
-// Git Internals that you will need to know to work with Git at this level,
-// check out [Chapter 10][pg] of the Pro Git book.
-//
-// [lg]: http://libgit2.github.com
-// [ap]: http://libgit2.github.com/libgit2
-// [pg]: https://git-scm.com/book/en/v2/Git-Internals-Plumbing-and-Porcelain
-
-// ### Includes
-
-// Including the `git2.h` header will include all the other libgit2 headers
-// that you need. It should be the only thing you need to include in order
-// to compile properly and get all the libgit2 API.
-#include <git2.h>
-#include <stdio.h>
-
-// Almost all libgit2 functions return 0 on success or negative on error.
-// This is not production quality error checking, but should be sufficient
-// as an example.
+/**
+ * [**libgit2**][lg] is a portable, pure C implementation of the Git core
+ * methods provided as a re-entrant linkable library with a solid API,
+ * allowing you to write native speed custom Git applications in any
+ * language which supports C bindings.
+ *
+ * This file is an example of using that API in a real, compilable C file.
+ * As the API is updated, this file will be updated to demonstrate the new
+ * functionality.
+ *
+ * If you're trying to write something in C using [libgit2][lg], you should
+ * also check out the generated [API documentation][ap]. We try to link to
+ * the relevant sections of the API docs in each section in this file.
+ *
+ * **libgit2** (for the most part) only implements the core plumbing
+ * functions, not really the higher level porcelain stuff. For a primer on
+ * Git Internals that you will need to know to work with Git at this level,
+ * check out [Chapter 10][pg] of the Pro Git book.
+ *
+ * [lg]: http://libgit2.github.com
+ * [ap]: http://libgit2.github.com/libgit2
+ * [pg]: https://git-scm.com/book/en/v2/Git-Internals-Plumbing-and-Porcelain
+ */
+
+#include "common.h"
+
+/**
+ * ### Includes
+ *
+ * Including the `git2.h` header will include all the other libgit2 headers
+ * that you need. It should be the only thing you need to include in order
+ * to compile properly and get all the libgit2 API.
+ */
+#include "git2.h"
+
+static void oid_parsing(git_oid *out);
+static void object_database(git_repository *repo, git_oid *oid);
+static void commit_writing(git_repository *repo);
+static void commit_parsing(git_repository *repo);
+static void tag_parsing(git_repository *repo);
+static void tree_parsing(git_repository *repo);
+static void blob_parsing(git_repository *repo);
+static void revwalking(git_repository *repo);
+static void index_walking(git_repository *repo);
+static void reference_listing(git_repository *repo);
+static void config_files(const char *repo_path, git_repository *repo);
+
+/**
+ * Almost all libgit2 functions return 0 on success or negative on error.
+ * This is not production quality error checking, but should be sufficient
+ * as an example.
+ */
static void check_error(int error_code, const char *action)
{
- const git_error *error = giterr_last();
+ const git_error *error = git_error_last();
if (!error_code)
return;
printf("Error %d %s - %s\n", error_code, action,
- (error && error->message) ? error->message : "???");
+ (error && error->message) ? error->message : "???");
exit(1);
}
-int main (int argc, char** argv)
+int lg2_general(git_repository *repo, int argc, char** argv)
+{
+ int error;
+ git_oid oid;
+ char *repo_path;
+
+ /**
+ * Initialize the library, this will set up any global state which libgit2 needs
+ * including threading and crypto
+ */
+ git_libgit2_init();
+
+ /**
+ * ### Opening the Repository
+ *
+ * There are a couple of methods for opening a repository, this being the
+ * simplest. There are also [methods][me] for specifying the index file
+ * and work tree locations, here we assume they are in the normal places.
+ *
+ * (Try running this program against tests/resources/testrepo.git.)
+ *
+ * [me]: http://libgit2.github.com/libgit2/#HEAD/group/repository
+ */
+ repo_path = (argc > 1) ? argv[1] : "/opt/libgit2-test/.git";
+
+ error = git_repository_open(&repo, repo_path);
+ check_error(error, "opening repository");
+
+ oid_parsing(&oid);
+ object_database(repo, &oid);
+ commit_writing(repo);
+ commit_parsing(repo);
+ tag_parsing(repo);
+ tree_parsing(repo);
+ blob_parsing(repo);
+ revwalking(repo);
+ index_walking(repo);
+ reference_listing(repo);
+ config_files(repo_path, repo);
+
+ /**
+ * Finally, when you're done with the repository, you can free it as well.
+ */
+ git_repository_free(repo);
+
+ return 0;
+}
+
+/**
+ * ### SHA-1 Value Conversions
+ */
+static void oid_parsing(git_oid *oid)
+{
+ char out[GIT_OID_HEXSZ+1];
+ char hex[] = "4a202b346bb0fb0db7eff3cffeb3c70babbd2045";
+
+ printf("*Hex to Raw*\n");
+
+ /**
+ * For our first example, we will convert a 40 character hex value to the
+ * 20 byte raw SHA1 value.
+ *
+ * The `git_oid` is the structure that keeps the SHA value. We will use
+ * this throughout the example for storing the value of the current SHA
+ * key we're working with.
+ */
+ git_oid_fromstr(oid, hex);
+
+ /*
+ * Once we've converted the string into the oid value, we can get the raw
+ * value of the SHA by accessing `oid.id`
+ *
+ * Next we will convert the 20 byte raw SHA1 value to a human readable 40
+ * char hex value.
+ */
+ printf("\n*Raw to Hex*\n");
+ out[GIT_OID_HEXSZ] = '\0';
+
+ /**
+ * If you have a oid, you can easily get the hex value of the SHA as well.
+ */
+ git_oid_fmt(out, oid);
+ printf("SHA hex string: %s\n", out);
+}
+
+/**
+ * ### Working with the Object Database
+ *
+ * **libgit2** provides [direct access][odb] to the object database. The
+ * object database is where the actual objects are stored in Git. For
+ * working with raw objects, we'll need to get this structure from the
+ * repository.
+ *
+ * [odb]: http://libgit2.github.com/libgit2/#HEAD/group/odb
+ */
+static void object_database(git_repository *repo, git_oid *oid)
{
- // Initialize the library, this will set up any global state which libgit2 needs
- // including threading and crypto
- git_libgit2_init();
-
- // ### Opening the Repository
-
- // There are a couple of methods for opening a repository, this being the
- // simplest. There are also [methods][me] for specifying the index file
- // and work tree locations, here we assume they are in the normal places.
- //
- // (Try running this program against tests/resources/testrepo.git.)
- //
- // [me]: http://libgit2.github.com/libgit2/#HEAD/group/repository
- int error;
- const char *repo_path = (argc > 1) ? argv[1] : "/opt/libgit2-test/.git";
- git_repository *repo;
-
- error = git_repository_open(&repo, repo_path);
- check_error(error, "opening repository");
-
- // ### SHA-1 Value Conversions
-
- // For our first example, we will convert a 40 character hex value to the
- // 20 byte raw SHA1 value.
- printf("*Hex to Raw*\n");
- char hex[] = "4a202b346bb0fb0db7eff3cffeb3c70babbd2045";
-
- // The `git_oid` is the structure that keeps the SHA value. We will use
- // this throughout the example for storing the value of the current SHA
- // key we're working with.
- git_oid oid;
- git_oid_fromstr(&oid, hex);
-
- // Once we've converted the string into the oid value, we can get the raw
- // value of the SHA by accessing `oid.id`
-
- // Next we will convert the 20 byte raw SHA1 value to a human readable 40
- // char hex value.
- printf("\n*Raw to Hex*\n");
- char out[GIT_OID_HEXSZ+1];
- out[GIT_OID_HEXSZ] = '\0';
-
- // If you have a oid, you can easily get the hex value of the SHA as well.
- git_oid_fmt(out, &oid);
- printf("SHA hex string: %s\n", out);
-
- // ### Working with the Object Database
-
- // **libgit2** provides [direct access][odb] to the object database. The
- // object database is where the actual objects are stored in Git. For
- // working with raw objects, we'll need to get this structure from the
- // repository.
- //
- // [odb]: http://libgit2.github.com/libgit2/#HEAD/group/odb
- git_odb *odb;
- git_repository_odb(&odb, repo);
-
- // #### Raw Object Reading
-
- printf("\n*Raw Object Read*\n");
- git_odb_object *obj;
- git_otype otype;
- const unsigned char *data;
- const char *str_type;
-
- // We can read raw objects directly from the object database if we have
- // the oid (SHA) of the object. This allows us to access objects without
- // knowing their type and inspect the raw bytes unparsed.
- error = git_odb_read(&obj, odb, &oid);
- check_error(error, "finding object in repository");
-
- // A raw object only has three properties - the type (commit, blob, tree
- // or tag), the size of the raw data and the raw, unparsed data itself.
- // For a commit or tag, that raw data is human readable plain ASCII
- // text. For a blob it is just file contents, so it could be text or
- // binary data. For a tree it is a special binary format, so it's unlikely
- // to be hugely helpful as a raw object.
- data = (const unsigned char *)git_odb_object_data(obj);
- otype = git_odb_object_type(obj);
-
- // We provide methods to convert from the object type which is an enum, to
- // a string representation of that value (and vice-versa).
- str_type = git_object_type2string(otype);
- printf("object length and type: %d, %s\n",
- (int)git_odb_object_size(obj),
- str_type);
-
- // For proper memory management, close the object when you are done with
- // it or it will leak memory.
- git_odb_object_free(obj);
-
- // #### Raw Object Writing
-
- printf("\n*Raw Object Write*\n");
-
- // You can also write raw object data to Git. This is pretty cool because
- // it gives you direct access to the key/value properties of Git. Here
- // we'll write a new blob object that just contains a simple string.
- // Notice that we have to specify the object type as the `git_otype` enum.
- git_odb_write(&oid, odb, "test data", sizeof("test data") - 1, GIT_OBJ_BLOB);
-
- // Now that we've written the object, we can check out what SHA1 was
- // generated when the object was written to our database.
- git_oid_fmt(out, &oid);
- printf("Written Object: %s\n", out);
-
- // ### Object Parsing
-
- // libgit2 has methods to parse every object type in Git so you don't have
- // to work directly with the raw data. This is much faster and simpler
- // than trying to deal with the raw data yourself.
-
- // #### Commit Parsing
-
- // [Parsing commit objects][pco] is simple and gives you access to all the
- // data in the commit - the author (name, email, datetime), committer
- // (same), tree, message, encoding and parent(s).
- //
- // [pco]: http://libgit2.github.com/libgit2/#HEAD/group/commit
-
- printf("\n*Commit Parsing*\n");
-
- git_commit *commit;
- git_oid_fromstr(&oid, "8496071c1b46c854b31185ea97743be6a8774479");
-
- error = git_commit_lookup(&commit, repo, &oid);
- check_error(error, "looking up commit");
-
- const git_signature *author, *cmtter;
- const char *message;
- time_t ctime;
- unsigned int parents, p;
-
- // Each of the properties of the commit object are accessible via methods,
- // including commonly needed variations, such as `git_commit_time` which
- // returns the author time and `git_commit_message` which gives you the
- // commit message (as a NUL-terminated string).
- message = git_commit_message(commit);
- author = git_commit_author(commit);
- cmtter = git_commit_committer(commit);
- ctime = git_commit_time(commit);
-
- // The author and committer methods return [git_signature] structures,
- // which give you name, email and `when`, which is a `git_time` structure,
- // giving you a timestamp and timezone offset.
- printf("Author: %s (%s)\n", author->name, author->email);
-
- // Commits can have zero or more parents. The first (root) commit will
- // have no parents, most commits will have one (i.e. the commit it was
- // based on) and merge commits will have two or more. Commits can
- // technically have any number, though it's rare to have more than two.
- parents = git_commit_parentcount(commit);
- for (p = 0;p < parents;p++) {
- git_commit *parent;
- git_commit_parent(&parent, commit, p);
- git_oid_fmt(out, git_commit_id(parent));
- printf("Parent: %s\n", out);
- git_commit_free(parent);
- }
-
- // Don't forget to close the object to prevent memory leaks. You will have
- // to do this for all the objects you open and parse.
- git_commit_free(commit);
-
- // #### Writing Commits
-
- // libgit2 provides a couple of methods to create commit objects easily as
- // well. There are four different create signatures, we'll just show one
- // of them here. You can read about the other ones in the [commit API
- // docs][cd].
- //
- // [cd]: http://libgit2.github.com/libgit2/#HEAD/group/commit
-
- printf("\n*Commit Writing*\n");
- git_oid tree_id, parent_id, commit_id;
- git_tree *tree;
- git_commit *parent;
-
- // Creating signatures for an authoring identity and time is simple. You
- // will need to do this to specify who created a commit and when. Default
- // values for the name and email should be found in the `user.name` and
- // `user.email` configuration options. See the `config` section of this
- // example file to see how to access config values.
- git_signature_new((git_signature **)&author,
- "Scott Chacon", "schacon@gmail.com", 123456789, 60);
- git_signature_new((git_signature **)&cmtter,
- "Scott A Chacon", "scott@github.com", 987654321, 90);
-
- // Commit objects need a tree to point to and optionally one or more
- // parents. Here we're creating oid objects to create the commit with,
- // but you can also use
- git_oid_fromstr(&tree_id, "f60079018b664e4e79329a7ef9559c8d9e0378d1");
- git_tree_lookup(&tree, repo, &tree_id);
- git_oid_fromstr(&parent_id, "5b5b025afb0b4c913b4c338a42934a3863bf3644");
- git_commit_lookup(&parent, repo, &parent_id);
-
- // Here we actually create the commit object with a single call with all
- // the values we need to create the commit. The SHA key is written to the
- // `commit_id` variable here.
- git_commit_create_v(
- &commit_id, /* out id */
- repo,
- NULL, /* do not update the HEAD */
- author,
- cmtter,
- NULL, /* use default message encoding */
- "example commit",
- tree,
- 1, parent);
-
- // Now we can take a look at the commit SHA we've generated.
- git_oid_fmt(out, &commit_id);
- printf("New Commit: %s\n", out);
-
- // #### Tag Parsing
-
- // You can parse and create tags with the [tag management API][tm], which
- // functions very similarly to the commit lookup, parsing and creation
- // methods, since the objects themselves are very similar.
- //
- // [tm]: http://libgit2.github.com/libgit2/#HEAD/group/tag
- printf("\n*Tag Parsing*\n");
- git_tag *tag;
- const char *tmessage, *tname;
- git_otype ttype;
-
- // We create an oid for the tag object if we know the SHA and look it up
- // the same way that we would a commit (or any other object).
- git_oid_fromstr(&oid, "b25fa35b38051e4ae45d4222e795f9df2e43f1d1");
-
- error = git_tag_lookup(&tag, repo, &oid);
- check_error(error, "looking up tag");
-
- // Now that we have the tag object, we can extract the information it
- // generally contains: the target (usually a commit object), the type of
- // the target object (usually 'commit'), the name ('v1.0'), the tagger (a
- // git_signature - name, email, timestamp), and the tag message.
- git_tag_target((git_object **)&commit, tag);
- tname = git_tag_name(tag); // "test"
- ttype = git_tag_target_type(tag); // GIT_OBJ_COMMIT (otype enum)
- tmessage = git_tag_message(tag); // "tag message\n"
- printf("Tag Message: %s\n", tmessage);
-
- git_commit_free(commit);
-
- // #### Tree Parsing
-
- // [Tree parsing][tp] is a bit different than the other objects, in that
- // we have a subtype which is the tree entry. This is not an actual
- // object type in Git, but a useful structure for parsing and traversing
- // tree entries.
- //
- // [tp]: http://libgit2.github.com/libgit2/#HEAD/group/tree
- printf("\n*Tree Parsing*\n");
-
- const git_tree_entry *entry;
- git_object *objt;
-
- // Create the oid and lookup the tree object just like the other objects.
- git_oid_fromstr(&oid, "2a741c18ac5ff082a7caaec6e74db3075a1906b5");
- git_tree_lookup(&tree, repo, &oid);
-
- // Getting the count of entries in the tree so you can iterate over them
- // if you want to.
- size_t cnt = git_tree_entrycount(tree); // 3
- printf("tree entries: %d\n", (int)cnt);
-
- entry = git_tree_entry_byindex(tree, 0);
- printf("Entry name: %s\n", git_tree_entry_name(entry)); // "hello.c"
-
- // You can also access tree entries by name if you know the name of the
- // entry you're looking for.
- entry = git_tree_entry_byname(tree, "README");
- git_tree_entry_name(entry); // "hello.c"
-
- // Once you have the entry object, you can access the content or subtree
- // (or commit, in the case of submodules) that it points to. You can also
- // get the mode if you want.
- git_tree_entry_to_object(&objt, repo, entry); // blob
-
- // Remember to close the looked-up object once you are done using it
- git_object_free(objt);
-
- // #### Blob Parsing
-
- // The last object type is the simplest and requires the least parsing
- // help. Blobs are just file contents and can contain anything, there is
- // no structure to it. The main advantage to using the [simple blob
- // api][ba] is that when you're creating blobs you don't have to calculate
- // the size of the content. There is also a helper for reading a file
- // from disk and writing it to the db and getting the oid back so you
- // don't have to do all those steps yourself.
- //
- // [ba]: http://libgit2.github.com/libgit2/#HEAD/group/blob
-
- printf("\n*Blob Parsing*\n");
- git_blob *blob;
-
- git_oid_fromstr(&oid, "1385f264afb75a56a5bec74243be9b367ba4ca08");
- git_blob_lookup(&blob, repo, &oid);
-
- // You can access a buffer with the raw contents of the blob directly.
- // Note that this buffer may not be contain ASCII data for certain blobs
- // (e.g. binary files): do not consider the buffer a NULL-terminated
- // string, and use the `git_blob_rawsize` attribute to find out its exact
- // size in bytes
- printf("Blob Size: %ld\n", (long)git_blob_rawsize(blob)); // 8
- git_blob_rawcontent(blob); // "content"
-
- // ### Revwalking
-
- // The libgit2 [revision walking api][rw] provides methods to traverse the
- // directed graph created by the parent pointers of the commit objects.
- // Since all commits point back to the commit that came directly before
- // them, you can walk this parentage as a graph and find all the commits
- // that were ancestors of (reachable from) a given starting point. This
- // can allow you to create `git log` type functionality.
- //
- // [rw]: http://libgit2.github.com/libgit2/#HEAD/group/revwalk
-
- printf("\n*Revwalking*\n");
- git_revwalk *walk;
- git_commit *wcommit;
-
- git_oid_fromstr(&oid, "5b5b025afb0b4c913b4c338a42934a3863bf3644");
-
- // To use the revwalker, create a new walker, tell it how you want to sort
- // the output and then push one or more starting points onto the walker.
- // If you want to emulate the output of `git log` you would push the SHA
- // of the commit that HEAD points to into the walker and then start
- // traversing them. You can also 'hide' commits that you want to stop at
- // or not see any of their ancestors. So if you want to emulate `git log
- // branch1..branch2`, you would push the oid of `branch2` and hide the oid
- // of `branch1`.
- git_revwalk_new(&walk, repo);
- git_revwalk_sorting(walk, GIT_SORT_TOPOLOGICAL | GIT_SORT_REVERSE);
- git_revwalk_push(walk, &oid);
-
- const git_signature *cauth;
- const char *cmsg;
-
- // Now that we have the starting point pushed onto the walker, we start
- // asking for ancestors. It will return them in the sorting order we asked
- // for as commit oids. We can then lookup and parse the committed pointed
- // at by the returned OID; note that this operation is specially fast
- // since the raw contents of the commit object will be cached in memory
- while ((git_revwalk_next(&oid, walk)) == 0) {
- error = git_commit_lookup(&wcommit, repo, &oid);
- check_error(error, "looking up commit during revwalk");
-
- cmsg = git_commit_message(wcommit);
- cauth = git_commit_author(wcommit);
- printf("%s (%s)\n", cmsg, cauth->email);
-
- git_commit_free(wcommit);
- }
-
- // Like the other objects, be sure to free the revwalker when you're done
- // to prevent memory leaks. Also, make sure that the repository being
- // walked it not deallocated while the walk is in progress, or it will
- // result in undefined behavior
- git_revwalk_free(walk);
-
- // ### Index File Manipulation
-
- // The [index file API][gi] allows you to read, traverse, update and write
- // the Git index file (sometimes thought of as the staging area).
- //
- // [gi]: http://libgit2.github.com/libgit2/#HEAD/group/index
-
- printf("\n*Index Walking*\n");
-
- git_index *index;
- unsigned int i, ecount;
-
- // You can either open the index from the standard location in an open
- // repository, as we're doing here, or you can open and manipulate any
- // index file with `git_index_open_bare()`. The index for the repository
- // will be located and loaded from disk.
- git_repository_index(&index, repo);
-
- // For each entry in the index, you can get a bunch of information
- // including the SHA (oid), path and mode which map to the tree objects
- // that are written out. It also has filesystem properties to help
- // determine what to inspect for changes (ctime, mtime, dev, ino, uid,
- // gid, file_size and flags) All these properties are exported publicly in
- // the `git_index_entry` struct
- ecount = git_index_entrycount(index);
- for (i = 0; i < ecount; ++i) {
- const git_index_entry *e = git_index_get_byindex(index, i);
-
- printf("path: %s\n", e->path);
- printf("mtime: %d\n", (int)e->mtime.seconds);
- printf("fs: %d\n", (int)e->file_size);
- }
-
- git_index_free(index);
-
- // ### References
-
- // The [reference API][ref] allows you to list, resolve, create and update
- // references such as branches, tags and remote references (everything in
- // the .git/refs directory).
- //
- // [ref]: http://libgit2.github.com/libgit2/#HEAD/group/reference
-
- printf("\n*Reference Listing*\n");
-
- // Here we will implement something like `git for-each-ref` simply listing
- // out all available references and the object SHA they resolve to.
- git_strarray ref_list;
- git_reference_list(&ref_list, repo);
-
- const char *refname;
- git_reference *ref;
-
- // Now that we have the list of reference names, we can lookup each ref
- // one at a time and resolve them to the SHA, then print both values out.
- for (i = 0; i < ref_list.count; ++i) {
- refname = ref_list.strings[i];
- git_reference_lookup(&ref, repo, refname);
-
- switch (git_reference_type(ref)) {
- case GIT_REF_OID:
- git_oid_fmt(out, git_reference_target(ref));
- printf("%s [%s]\n", refname, out);
- break;
-
- case GIT_REF_SYMBOLIC:
- printf("%s => %s\n", refname, git_reference_symbolic_target(ref));
- break;
- default:
- fprintf(stderr, "Unexpected reference type\n");
- exit(1);
- }
- }
-
- git_strarray_free(&ref_list);
-
- // ### Config Files
-
- // The [config API][config] allows you to list and updatee config values
- // in any of the accessible config file locations (system, global, local).
- //
- // [config]: http://libgit2.github.com/libgit2/#HEAD/group/config
+ char oid_hex[GIT_OID_HEXSZ+1] = { 0 };
+ const unsigned char *data;
+ const char *str_type;
+ int error;
+ git_odb_object *obj;
+ git_odb *odb;
+ git_object_t otype;
+
+ git_repository_odb(&odb, repo);
+
+ /**
+ * #### Raw Object Reading
+ */
+
+ printf("\n*Raw Object Read*\n");
+
+ /**
+ * We can read raw objects directly from the object database if we have
+ * the oid (SHA) of the object. This allows us to access objects without
+ * knowing their type and inspect the raw bytes unparsed.
+ */
+ error = git_odb_read(&obj, odb, oid);
+ check_error(error, "finding object in repository");
+
+ /**
+ * A raw object only has three properties - the type (commit, blob, tree
+ * or tag), the size of the raw data and the raw, unparsed data itself.
+ * For a commit or tag, that raw data is human readable plain ASCII
+ * text. For a blob it is just file contents, so it could be text or
+ * binary data. For a tree it is a special binary format, so it's unlikely
+ * to be hugely helpful as a raw object.
+ */
+ data = (const unsigned char *)git_odb_object_data(obj);
+ otype = git_odb_object_type(obj);
+
+ /**
+ * We provide methods to convert from the object type which is an enum, to
+ * a string representation of that value (and vice-versa).
+ */
+ str_type = git_object_type2string(otype);
+ printf("object length and type: %d, %s\nobject data: %s\n",
+ (int)git_odb_object_size(obj),
+ str_type, data);
+
+ /**
+ * For proper memory management, close the object when you are done with
+ * it or it will leak memory.
+ */
+ git_odb_object_free(obj);
+
+ /**
+ * #### Raw Object Writing
+ */
+
+ printf("\n*Raw Object Write*\n");
+
+ /**
+ * You can also write raw object data to Git. This is pretty cool because
+ * it gives you direct access to the key/value properties of Git. Here
+ * we'll write a new blob object that just contains a simple string.
+ * Notice that we have to specify the object type as the `git_otype` enum.
+ */
+ git_odb_write(oid, odb, "test data", sizeof("test data") - 1, GIT_OBJECT_BLOB);
+
+ /**
+ * Now that we've written the object, we can check out what SHA1 was
+ * generated when the object was written to our database.
+ */
+ git_oid_fmt(oid_hex, oid);
+ printf("Written Object: %s\n", oid_hex);
+
+ /**
+ * Free the object database after usage.
+ */
+ git_odb_free(odb);
+}
- printf("\n*Config Listing*\n");
+/**
+ * #### Writing Commits
+ *
+ * libgit2 provides a couple of methods to create commit objects easily as
+ * well. There are four different create signatures, we'll just show one
+ * of them here. You can read about the other ones in the [commit API
+ * docs][cd].
+ *
+ * [cd]: http://libgit2.github.com/libgit2/#HEAD/group/commit
+ */
+static void commit_writing(git_repository *repo)
+{
+ git_oid tree_id, parent_id, commit_id;
+ git_tree *tree;
+ git_commit *parent;
+ git_signature *author, *committer;
+ char oid_hex[GIT_OID_HEXSZ+1] = { 0 };
+
+ printf("\n*Commit Writing*\n");
+
+ /**
+ * Creating signatures for an authoring identity and time is simple. You
+ * will need to do this to specify who created a commit and when. Default
+ * values for the name and email should be found in the `user.name` and
+ * `user.email` configuration options. See the `config` section of this
+ * example file to see how to access config values.
+ */
+ git_signature_new(&author,
+ "Scott Chacon", "schacon@gmail.com", 123456789, 60);
+ git_signature_new(&committer,
+ "Scott A Chacon", "scott@github.com", 987654321, 90);
+
+ /**
+ * Commit objects need a tree to point to and optionally one or more
+ * parents. Here we're creating oid objects to create the commit with,
+ * but you can also use
+ */
+ git_oid_fromstr(&tree_id, "f60079018b664e4e79329a7ef9559c8d9e0378d1");
+ git_tree_lookup(&tree, repo, &tree_id);
+ git_oid_fromstr(&parent_id, "5b5b025afb0b4c913b4c338a42934a3863bf3644");
+ git_commit_lookup(&parent, repo, &parent_id);
+
+ /**
+ * Here we actually create the commit object with a single call with all
+ * the values we need to create the commit. The SHA key is written to the
+ * `commit_id` variable here.
+ */
+ git_commit_create_v(
+ &commit_id, /* out id */
+ repo,
+ NULL, /* do not update the HEAD */
+ author,
+ committer,
+ NULL, /* use default message encoding */
+ "example commit",
+ tree,
+ 1, parent);
+
+ /**
+ * Now we can take a look at the commit SHA we've generated.
+ */
+ git_oid_fmt(oid_hex, &commit_id);
+ printf("New Commit: %s\n", oid_hex);
+
+ /**
+ * Free all objects used in the meanwhile.
+ */
+ git_tree_free(tree);
+ git_commit_free(parent);
+ git_signature_free(author);
+ git_signature_free(committer);
+}
+
+/**
+ * ### Object Parsing
+ *
+ * libgit2 has methods to parse every object type in Git so you don't have
+ * to work directly with the raw data. This is much faster and simpler
+ * than trying to deal with the raw data yourself.
+ */
+
+/**
+ * #### Commit Parsing
+ *
+ * [Parsing commit objects][pco] is simple and gives you access to all the
+ * data in the commit - the author (name, email, datetime), committer
+ * (same), tree, message, encoding and parent(s).
+ *
+ * [pco]: http://libgit2.github.com/libgit2/#HEAD/group/commit
+ */
+static void commit_parsing(git_repository *repo)
+{
+ const git_signature *author, *cmtter;
+ git_commit *commit, *parent;
+ git_oid oid;
+ char oid_hex[GIT_OID_HEXSZ+1];
+ const char *message;
+ unsigned int parents, p;
+ int error;
+ time_t time;
+
+ printf("\n*Commit Parsing*\n");
+
+ git_oid_fromstr(&oid, "8496071c1b46c854b31185ea97743be6a8774479");
+
+ error = git_commit_lookup(&commit, repo, &oid);
+ check_error(error, "looking up commit");
+
+ /**
+ * Each of the properties of the commit object are accessible via methods,
+ * including commonly needed variations, such as `git_commit_time` which
+ * returns the author time and `git_commit_message` which gives you the
+ * commit message (as a NUL-terminated string).
+ */
+ message = git_commit_message(commit);
+ author = git_commit_author(commit);
+ cmtter = git_commit_committer(commit);
+ time = git_commit_time(commit);
+
+ /**
+ * The author and committer methods return [git_signature] structures,
+ * which give you name, email and `when`, which is a `git_time` structure,
+ * giving you a timestamp and timezone offset.
+ */
+ printf("Author: %s (%s)\nCommitter: %s (%s)\nDate: %s\nMessage: %s\n",
+ author->name, author->email,
+ cmtter->name, cmtter->email,
+ ctime(&time), message);
+
+ /**
+ * Commits can have zero or more parents. The first (root) commit will
+ * have no parents, most commits will have one (i.e. the commit it was
+ * based on) and merge commits will have two or more. Commits can
+ * technically have any number, though it's rare to have more than two.
+ */
+ parents = git_commit_parentcount(commit);
+ for (p = 0;p < parents;p++) {
+ memset(oid_hex, 0, sizeof(oid_hex));
+
+ git_commit_parent(&parent, commit, p);
+ git_oid_fmt(oid_hex, git_commit_id(parent));
+ printf("Parent: %s\n", oid_hex);
+ git_commit_free(parent);
+ }
+
+ git_commit_free(commit);
+}
- const char *email;
- int32_t j;
+/**
+ * #### Tag Parsing
+ *
+ * You can parse and create tags with the [tag management API][tm], which
+ * functions very similarly to the commit lookup, parsing and creation
+ * methods, since the objects themselves are very similar.
+ *
+ * [tm]: http://libgit2.github.com/libgit2/#HEAD/group/tag
+ */
+static void tag_parsing(git_repository *repo)
+{
+ git_commit *commit;
+ git_object_t type;
+ git_tag *tag;
+ git_oid oid;
+ const char *name, *message;
+ int error;
+
+ printf("\n*Tag Parsing*\n");
+
+ /**
+ * We create an oid for the tag object if we know the SHA and look it up
+ * the same way that we would a commit (or any other object).
+ */
+ git_oid_fromstr(&oid, "b25fa35b38051e4ae45d4222e795f9df2e43f1d1");
+
+ error = git_tag_lookup(&tag, repo, &oid);
+ check_error(error, "looking up tag");
+
+ /**
+ * Now that we have the tag object, we can extract the information it
+ * generally contains: the target (usually a commit object), the type of
+ * the target object (usually 'commit'), the name ('v1.0'), the tagger (a
+ * git_signature - name, email, timestamp), and the tag message.
+ */
+ git_tag_target((git_object **)&commit, tag);
+ name = git_tag_name(tag); /* "test" */
+ type = git_tag_target_type(tag); /* GIT_OBJECT_COMMIT (object_t enum) */
+ message = git_tag_message(tag); /* "tag message\n" */
+ printf("Tag Name: %s\nTag Type: %s\nTag Message: %s\n",
+ name, git_object_type2string(type), message);
+
+ /**
+ * Free both the commit and tag after usage.
+ */
+ git_commit_free(commit);
+ git_tag_free(tag);
+}
- git_config *cfg;
+/**
+ * #### Tree Parsing
+ *
+ * [Tree parsing][tp] is a bit different than the other objects, in that
+ * we have a subtype which is the tree entry. This is not an actual
+ * object type in Git, but a useful structure for parsing and traversing
+ * tree entries.
+ *
+ * [tp]: http://libgit2.github.com/libgit2/#HEAD/group/tree
+ */
+static void tree_parsing(git_repository *repo)
+{
+ const git_tree_entry *entry;
+ size_t cnt;
+ git_object *obj;
+ git_tree *tree;
+ git_oid oid;
+
+ printf("\n*Tree Parsing*\n");
+
+ /**
+ * Create the oid and lookup the tree object just like the other objects.
+ */
+ git_oid_fromstr(&oid, "f60079018b664e4e79329a7ef9559c8d9e0378d1");
+ git_tree_lookup(&tree, repo, &oid);
+
+ /**
+ * Getting the count of entries in the tree so you can iterate over them
+ * if you want to.
+ */
+ cnt = git_tree_entrycount(tree); /* 2 */
+ printf("tree entries: %d\n", (int) cnt);
+
+ entry = git_tree_entry_byindex(tree, 0);
+ printf("Entry name: %s\n", git_tree_entry_name(entry)); /* "README" */
+
+ /**
+ * You can also access tree entries by name if you know the name of the
+ * entry you're looking for.
+ */
+ entry = git_tree_entry_byname(tree, "README");
+ git_tree_entry_name(entry); /* "README" */
+
+ /**
+ * Once you have the entry object, you can access the content or subtree
+ * (or commit, in the case of submodules) that it points to. You can also
+ * get the mode if you want.
+ */
+ git_tree_entry_to_object(&obj, repo, entry); /* blob */
+
+ /**
+ * Remember to close the looked-up object and tree once you are done using it
+ */
+ git_object_free(obj);
+ git_tree_free(tree);
+}
- // Open a config object so we can read global values from it.
- char config_path[256];
- sprintf(config_path, "%s/config", repo_path);
- check_error(git_config_open_ondisk(&cfg, config_path), "opening config");
+/**
+ * #### Blob Parsing
+ *
+ * The last object type is the simplest and requires the least parsing
+ * help. Blobs are just file contents and can contain anything, there is
+ * no structure to it. The main advantage to using the [simple blob
+ * api][ba] is that when you're creating blobs you don't have to calculate
+ * the size of the content. There is also a helper for reading a file
+ * from disk and writing it to the db and getting the oid back so you
+ * don't have to do all those steps yourself.
+ *
+ * [ba]: http://libgit2.github.com/libgit2/#HEAD/group/blob
+ */
+static void blob_parsing(git_repository *repo)
+{
+ git_blob *blob;
+ git_oid oid;
+
+ printf("\n*Blob Parsing*\n");
+
+ git_oid_fromstr(&oid, "1385f264afb75a56a5bec74243be9b367ba4ca08");
+ git_blob_lookup(&blob, repo, &oid);
+
+ /**
+ * You can access a buffer with the raw contents of the blob directly.
+ * Note that this buffer may not be contain ASCII data for certain blobs
+ * (e.g. binary files): do not consider the buffer a NULL-terminated
+ * string, and use the `git_blob_rawsize` attribute to find out its exact
+ * size in bytes
+ * */
+ printf("Blob Size: %ld\n", (long)git_blob_rawsize(blob)); /* 8 */
+ git_blob_rawcontent(blob); /* "content" */
+
+ /**
+ * Free the blob after usage.
+ */
+ git_blob_free(blob);
+}
- git_config_get_int32(&j, cfg, "help.autocorrect");
- printf("Autocorrect: %d\n", j);
+/**
+ * ### Revwalking
+ *
+ * The libgit2 [revision walking api][rw] provides methods to traverse the
+ * directed graph created by the parent pointers of the commit objects.
+ * Since all commits point back to the commit that came directly before
+ * them, you can walk this parentage as a graph and find all the commits
+ * that were ancestors of (reachable from) a given starting point. This
+ * can allow you to create `git log` type functionality.
+ *
+ * [rw]: http://libgit2.github.com/libgit2/#HEAD/group/revwalk
+ */
+static void revwalking(git_repository *repo)
+{
+ const git_signature *cauth;
+ const char *cmsg;
+ int error;
+ git_revwalk *walk;
+ git_commit *wcommit;
+ git_oid oid;
+
+ printf("\n*Revwalking*\n");
+
+ git_oid_fromstr(&oid, "5b5b025afb0b4c913b4c338a42934a3863bf3644");
+
+ /**
+ * To use the revwalker, create a new walker, tell it how you want to sort
+ * the output and then push one or more starting points onto the walker.
+ * If you want to emulate the output of `git log` you would push the SHA
+ * of the commit that HEAD points to into the walker and then start
+ * traversing them. You can also 'hide' commits that you want to stop at
+ * or not see any of their ancestors. So if you want to emulate `git log
+ * branch1..branch2`, you would push the oid of `branch2` and hide the oid
+ * of `branch1`.
+ */
+ git_revwalk_new(&walk, repo);
+ git_revwalk_sorting(walk, GIT_SORT_TOPOLOGICAL | GIT_SORT_REVERSE);
+ git_revwalk_push(walk, &oid);
+
+ /**
+ * Now that we have the starting point pushed onto the walker, we start
+ * asking for ancestors. It will return them in the sorting order we asked
+ * for as commit oids. We can then lookup and parse the committed pointed
+ * at by the returned OID; note that this operation is specially fast
+ * since the raw contents of the commit object will be cached in memory
+ */
+ while ((git_revwalk_next(&oid, walk)) == 0) {
+ error = git_commit_lookup(&wcommit, repo, &oid);
+ check_error(error, "looking up commit during revwalk");
+
+ cmsg = git_commit_message(wcommit);
+ cauth = git_commit_author(wcommit);
+ printf("%s (%s)\n", cmsg, cauth->email);
+
+ git_commit_free(wcommit);
+ }
+
+ /**
+ * Like the other objects, be sure to free the revwalker when you're done
+ * to prevent memory leaks. Also, make sure that the repository being
+ * walked it not deallocated while the walk is in progress, or it will
+ * result in undefined behavior
+ */
+ git_revwalk_free(walk);
+}
- git_config_get_string(&email, cfg, "user.email");
- printf("Email: %s\n", email);
+/**
+ * ### Index File Manipulation *
+ * The [index file API][gi] allows you to read, traverse, update and write
+ * the Git index file (sometimes thought of as the staging area).
+ *
+ * [gi]: http://libgit2.github.com/libgit2/#HEAD/group/index
+ */
+static void index_walking(git_repository *repo)
+{
+ git_index *index;
+ size_t i, ecount;
+
+ printf("\n*Index Walking*\n");
+
+ /**
+ * You can either open the index from the standard location in an open
+ * repository, as we're doing here, or you can open and manipulate any
+ * index file with `git_index_open_bare()`. The index for the repository
+ * will be located and loaded from disk.
+ */
+ git_repository_index(&index, repo);
+
+ /**
+ * For each entry in the index, you can get a bunch of information
+ * including the SHA (oid), path and mode which map to the tree objects
+ * that are written out. It also has filesystem properties to help
+ * determine what to inspect for changes (ctime, mtime, dev, ino, uid,
+ * gid, file_size and flags) All these properties are exported publicly in
+ * the `git_index_entry` struct
+ */
+ ecount = git_index_entrycount(index);
+ for (i = 0; i < ecount; ++i) {
+ const git_index_entry *e = git_index_get_byindex(index, i);
+
+ printf("path: %s\n", e->path);
+ printf("mtime: %d\n", (int)e->mtime.seconds);
+ printf("fs: %d\n", (int)e->file_size);
+ }
+
+ git_index_free(index);
+}
- // Finally, when you're done with the repository, you can free it as well.
- git_repository_free(repo);
+/**
+ * ### References
+ *
+ * The [reference API][ref] allows you to list, resolve, create and update
+ * references such as branches, tags and remote references (everything in
+ * the .git/refs directory).
+ *
+ * [ref]: http://libgit2.github.com/libgit2/#HEAD/group/reference
+ */
+static void reference_listing(git_repository *repo)
+{
+ git_strarray ref_list;
+ unsigned i;
+
+ printf("\n*Reference Listing*\n");
+
+ /**
+ * Here we will implement something like `git for-each-ref` simply listing
+ * out all available references and the object SHA they resolve to.
+ *
+ * Now that we have the list of reference names, we can lookup each ref
+ * one at a time and resolve them to the SHA, then print both values out.
+ */
+
+ git_reference_list(&ref_list, repo);
+
+ for (i = 0; i < ref_list.count; ++i) {
+ git_reference *ref;
+ char oid_hex[GIT_OID_HEXSZ+1] = GIT_OID_HEX_ZERO;
+ const char *refname;
+
+ refname = ref_list.strings[i];
+ git_reference_lookup(&ref, repo, refname);
+
+ switch (git_reference_type(ref)) {
+ case GIT_REFERENCE_DIRECT:
+ git_oid_fmt(oid_hex, git_reference_target(ref));
+ printf("%s [%s]\n", refname, oid_hex);
+ break;
+
+ case GIT_REFERENCE_SYMBOLIC:
+ printf("%s => %s\n", refname, git_reference_symbolic_target(ref));
+ break;
+ default:
+ fprintf(stderr, "Unexpected reference type\n");
+ exit(1);
+ }
+
+ git_reference_free(ref);
+ }
+
+ git_strarray_dispose(&ref_list);
+}
- return 0;
+/**
+ * ### Config Files
+ *
+ * The [config API][config] allows you to list and update config values
+ * in any of the accessible config file locations (system, global, local).
+ *
+ * [config]: http://libgit2.github.com/libgit2/#HEAD/group/config
+ */
+static void config_files(const char *repo_path, git_repository* repo)
+{
+ const char *email;
+ char config_path[256];
+ int32_t autocorrect;
+ git_config *cfg;
+ git_config *snap_cfg;
+ int error_code;
+
+ printf("\n*Config Listing*\n");
+
+ /**
+ * Open a config object so we can read global values from it.
+ */
+ sprintf(config_path, "%s/config", repo_path);
+ check_error(git_config_open_ondisk(&cfg, config_path), "opening config");
+
+ if (git_config_get_int32(&autocorrect, cfg, "help.autocorrect") == 0)
+ printf("Autocorrect: %d\n", autocorrect);
+
+ check_error(git_repository_config_snapshot(&snap_cfg, repo), "config snapshot");
+ git_config_get_string(&email, snap_cfg, "user.email");
+ printf("Email: %s\n", email);
+
+ error_code = git_config_get_int32(&autocorrect, cfg, "help.autocorrect");
+ switch (error_code)
+ {
+ case 0:
+ printf("Autocorrect: %d\n", autocorrect);
+ break;
+ case GIT_ENOTFOUND:
+ printf("Autocorrect: Undefined\n");
+ break;
+ default:
+ check_error(error_code, "get_int32 failed");
+ }
+ git_config_free(cfg);
+
+ check_error(git_repository_config_snapshot(&snap_cfg, repo), "config snapshot");
+ error_code = git_config_get_string(&email, snap_cfg, "user.email");
+ switch (error_code)
+ {
+ case 0:
+ printf("Email: %s\n", email);
+ break;
+ case GIT_ENOTFOUND:
+ printf("Email: Undefined\n");
+ break;
+ default:
+ check_error(error_code, "get_string failed");
+ }
+
+ git_config_free(snap_cfg);
}
projects / libgit2.git / blobdiff