src/reflog.c - third_party/libgit2 - Git at Google

 /*
  * Copyright (C) 2009-2012 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.
  */

 #include "reflog.h"
 #include "repository.h"
 #include "filebuf.h"
 #include "signature.h"

 static int reflog_init(git_reflog **reflog, git_reference *ref)
 {
 	git_reflog *log;

 	*reflog = NULL;

 	log = git__calloc(1, sizeof(git_reflog));
 	GITERR_CHECK_ALLOC(log);

 	log->ref_name = git__strdup(ref->name);
 	GITERR_CHECK_ALLOC(log->ref_name);

 	if (git_vector_init(&log->entries, 0, NULL) < 0) {
 		git__free(log->ref_name);
 		git__free(log);
 		return -1;
 	}

 	*reflog = log;

 	return 0;
 }

 static int reflog_write(const char *log_path, const char *oid_old,
 			const char *oid_new, const git_signature *committer,
 			const char *msg)
 {
 	int error;
 	git_buf log = GIT_BUF_INIT;
 	git_filebuf fbuf = GIT_FILEBUF_INIT;
 	bool trailing_newline = false;

 	assert(log_path && oid_old && oid_new && committer);

 	if (msg) {
 		const char *newline = strchr(msg, '\n');
 		if (newline) {
 			if (*(newline + 1) == '\0')
 				trailing_newline = true;
 			else {
 				giterr_set(GITERR_INVALID, "Reflog message cannot contain newline");
 				return -1;
 			}
 		}
 	}

 	git_buf_puts(&log, oid_old);
 	git_buf_putc(&log, ' ');

 	git_buf_puts(&log, oid_new);

 	git_signature__writebuf(&log, " ", committer);
 	git_buf_truncate(&log, log.size - 1); /* drop LF */

 	if (msg) {
 		git_buf_putc(&log, '\t');
 		git_buf_puts(&log, msg);
 	}

 	if (!trailing_newline)
 		git_buf_putc(&log, '\n');

 	if (git_buf_oom(&log)) {
 		git_buf_free(&log);
 		return -1;
 	}

 	error = git_filebuf_open(&fbuf, log_path, GIT_FILEBUF_APPEND);
 	if (!error) {
 		if ((error = git_filebuf_write(&fbuf, log.ptr, log.size)) < 0)
 			git_filebuf_cleanup(&fbuf);
 		else
 			error = git_filebuf_commit(&fbuf, GIT_REFLOG_FILE_MODE);
 	}

 	git_buf_free(&log);

 	return error;
 }

 static int reflog_parse(git_reflog *log, const char *buf, size_t buf_size)
 {
 	const char *ptr;
 	git_reflog_entry *entry;

 #define seek_forward(_increase) do { \
 	if (_increase >= buf_size) { \
 		giterr_set(GITERR_INVALID, "Ran out of data while parsing reflog"); \
 		goto fail; \
 	} \
 	buf += _increase; \
 	buf_size -= _increase; \
 	} while (0)

 	while (buf_size > GIT_REFLOG_SIZE_MIN) {
 		entry = git__malloc(sizeof(git_reflog_entry));
 		GITERR_CHECK_ALLOC(entry);

 		entry->committer = git__malloc(sizeof(git_signature));
 		GITERR_CHECK_ALLOC(entry->committer);

 		if (git_oid_fromstrn(&entry->oid_old, buf, GIT_OID_HEXSZ) < 0)
 			goto fail;
 		seek_forward(GIT_OID_HEXSZ + 1);

 		if (git_oid_fromstrn(&entry->oid_cur, buf, GIT_OID_HEXSZ) < 0)
 			goto fail;
 		seek_forward(GIT_OID_HEXSZ + 1);

 		ptr = buf;

 		/* Seek forward to the end of the signature. */
 		while (*buf && *buf != '\t' && *buf != '\n')
 			seek_forward(1);

 		if (git_signature__parse(entry->committer, &ptr, buf + 1, NULL, *buf) < 0)
 			goto fail;

 		if (*buf == '\t') {
 			/* We got a message. Read everything till we reach LF. */
 			seek_forward(1);
 			ptr = buf;

 			while (*buf && *buf != '\n')
 				seek_forward(1);

 			entry->msg = git__strndup(ptr, buf - ptr);
 			GITERR_CHECK_ALLOC(entry->msg);
 		} else
 			entry->msg = NULL;

 		while (*buf && *buf == '\n' && buf_size > 1)
 			seek_forward(1);

 		if (git_vector_insert(&log->entries, entry) < 0)
 			goto fail;
 	}

 	return 0;

 #undef seek_forward

 fail:
 	if (entry) {
 		git__free(entry->committer);
 		git__free(entry);
 	}
 	return -1;
 }

 void git_reflog_free(git_reflog *reflog)
 {
 	unsigned int i;
 	git_reflog_entry *entry;

 	for (i=0; i < reflog->entries.length; i++) {
 		entry = git_vector_get(&reflog->entries, i);

 		git_signature_free(entry->committer);

 		git__free(entry->msg);
 		git__free(entry);
 	}

 	git_vector_free(&reflog->entries);
 	git__free(reflog->ref_name);
 	git__free(reflog);
 }

 int git_reflog_read(git_reflog **reflog, git_reference *ref)
 {
 	int error;
 	git_buf log_path = GIT_BUF_INIT;
 	git_buf log_file = GIT_BUF_INIT;
 	git_reflog *log = NULL;

 	*reflog = NULL;

 	if (reflog_init(&log, ref) < 0)
 		return -1;

 	error = git_buf_join_n(&log_path, '/', 3,
 		ref->owner->path_repository, GIT_REFLOG_DIR, ref->name);

 	if (!error)
 		error = git_futils_readbuffer(&log_file, log_path.ptr);

 	if (!error)
 		error = reflog_parse(log, log_file.ptr, log_file.size);

 	if (!error)
 		*reflog = log;
 	else
 		git_reflog_free(log);

 	git_buf_free(&log_file);
 	git_buf_free(&log_path);

 	return error;
 }

 int git_reflog_write(git_reference *ref, const git_oid *oid_old,
 				const git_signature *committer, const char *msg)
 {
 	int error;
 	char old[GIT_OID_HEXSZ+1];
 	char new[GIT_OID_HEXSZ+1];
 	git_buf log_path = GIT_BUF_INIT;
 	git_reference *r;
 	const git_oid *oid;

 	if ((error = git_reference_resolve(&r, ref)) < 0)
 		return error;

 	oid = git_reference_oid(r);
 	if (oid == NULL) {
 		giterr_set(GITERR_REFERENCE,
 			"Failed to write reflog. Cannot resolve reference `%s`", r->name);
 		git_reference_free(r);
 		return -1;
 	}

 	git_oid_tostr(new, GIT_OID_HEXSZ+1, oid);

 	git_reference_free(r);

 	error = git_buf_join_n(&log_path, '/', 3,
 		ref->owner->path_repository, GIT_REFLOG_DIR, ref->name);
 	if (error < 0)
 		goto cleanup;

 	if (git_path_exists(log_path.ptr) == false) {
 		error = git_futils_mkpath2file(log_path.ptr, GIT_REFLOG_DIR_MODE);
 	} else if (git_path_isfile(log_path.ptr) == false) {
 		giterr_set(GITERR_REFERENCE,
 			"Failed to write reflog. `%s` is directory", log_path.ptr);
 		error = -1;
 	} else if (oid_old == NULL) {
 		giterr_set(GITERR_REFERENCE,
 			"Failed to write reflog. Old OID cannot be NULL for existing reference");
 		error = -1;
 	}
 	if (error < 0)
 		goto cleanup;

 	if (oid_old)
 		git_oid_tostr(old, sizeof(old), oid_old);
 	else
 		p_snprintf(old, sizeof(old), "%0*d", GIT_OID_HEXSZ, 0);

 	error = reflog_write(log_path.ptr, old, new, committer, msg);

 cleanup:
 	git_buf_free(&log_path);
 	return error;
 }

 int git_reflog_rename(git_reference *ref, const char *new_name)
 {
 	int error;
 	git_buf old_path = GIT_BUF_INIT;
 	git_buf new_path = GIT_BUF_INIT;

 	if (!git_buf_join_n(&old_path, '/', 3, ref->owner->path_repository,
 			GIT_REFLOG_DIR, ref->name) &&
 		!git_buf_join_n(&new_path, '/', 3, ref->owner->path_repository,
 			GIT_REFLOG_DIR, new_name))
 		error = p_rename(git_buf_cstr(&old_path), git_buf_cstr(&new_path));
 	else
 		error = -1;

 	git_buf_free(&old_path);
 	git_buf_free(&new_path);

 	return error;
 }

 int git_reflog_delete(git_reference *ref)
 {
 	int error;
 	git_buf path = GIT_BUF_INIT;

 	error = git_buf_join_n(
 		&path, '/', 3, ref->owner->path_repository, GIT_REFLOG_DIR, ref->name);

 	if (!error && git_path_exists(path.ptr))
 		error = p_unlink(path.ptr);

 	git_buf_free(&path);

 	return error;
 }

 unsigned int git_reflog_entrycount(git_reflog *reflog)
 {
 	assert(reflog);
 	return reflog->entries.length;
 }

 const git_reflog_entry * git_reflog_entry_byindex(git_reflog *reflog, unsigned int idx)
 {
 	assert(reflog);
 	return git_vector_get(&reflog->entries, idx);
 }

 const git_oid * git_reflog_entry_oidold(const git_reflog_entry *entry)
 {
 	assert(entry);
 	return &entry->oid_old;
 }

 const git_oid * git_reflog_entry_oidnew(const git_reflog_entry *entry)
 {
 	assert(entry);
 	return &entry->oid_cur;
 }

 git_signature * git_reflog_entry_committer(const git_reflog_entry *entry)
 {
 	assert(entry);
 	return entry->committer;
 }

 char * git_reflog_entry_msg(const git_reflog_entry *entry)
 {
 	assert(entry);
 	return entry->msg;
 }
	/*
	* Copyright (C) 2009-2012 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.
	*/

	#include "reflog.h"
	#include "repository.h"
	#include "filebuf.h"
	#include "signature.h"

	static int reflog_init(git_reflog *reflog, git_reference ref)
	{
	git_reflog *log;

	*reflog = NULL;

	log = git__calloc(1, sizeof(git_reflog));
	GITERR_CHECK_ALLOC(log);

	log->ref_name = git__strdup(ref->name);
	GITERR_CHECK_ALLOC(log->ref_name);

	if (git_vector_init(&log->entries, 0, NULL) < 0) {
	git__free(log->ref_name);
	git__free(log);
	return -1;
	}

	*reflog = log;

	return 0;
	}

	static int reflog_write(const char log_path, const char oid_old,
	const char oid_new, const git_signature committer,
	const char *msg)
	{
	int error;
	git_buf log = GIT_BUF_INIT;
	git_filebuf fbuf = GIT_FILEBUF_INIT;
	bool trailing_newline = false;

	assert(log_path && oid_old && oid_new && committer);

	if (msg) {
	const char *newline = strchr(msg, '\n');
	if (newline) {
	if (*(newline + 1) == '\0')
	trailing_newline = true;
	else {
	giterr_set(GITERR_INVALID, "Reflog message cannot contain newline");
	return -1;
	}
	}
	}

	git_buf_puts(&log, oid_old);
	git_buf_putc(&log, ' ');

	git_buf_puts(&log, oid_new);

	git_signature__writebuf(&log, " ", committer);
	git_buf_truncate(&log, log.size - 1); /* drop LF */

	if (msg) {
	git_buf_putc(&log, '\t');
	git_buf_puts(&log, msg);
	}

	if (!trailing_newline)
	git_buf_putc(&log, '\n');

	if (git_buf_oom(&log)) {
	git_buf_free(&log);
	return -1;
	}

	error = git_filebuf_open(&fbuf, log_path, GIT_FILEBUF_APPEND);
	if (!error) {
	if ((error = git_filebuf_write(&fbuf, log.ptr, log.size)) < 0)
	git_filebuf_cleanup(&fbuf);
	else
	error = git_filebuf_commit(&fbuf, GIT_REFLOG_FILE_MODE);
	}

	git_buf_free(&log);

	return error;
	}

	static int reflog_parse(git_reflog log, const char buf, size_t buf_size)
	{
	const char *ptr;
	git_reflog_entry *entry;

	#define seek_forward(_increase) do { \
	if (_increase >= buf_size) { \
	giterr_set(GITERR_INVALID, "Ran out of data while parsing reflog"); \
	goto fail; \
	} \
	buf += _increase; \
	buf_size -= _increase; \
	} while (0)

	while (buf_size > GIT_REFLOG_SIZE_MIN) {
	entry = git__malloc(sizeof(git_reflog_entry));
	GITERR_CHECK_ALLOC(entry);

	entry->committer = git__malloc(sizeof(git_signature));
	GITERR_CHECK_ALLOC(entry->committer);

	if (git_oid_fromstrn(&entry->oid_old, buf, GIT_OID_HEXSZ) < 0)
	goto fail;
	seek_forward(GIT_OID_HEXSZ + 1);

	if (git_oid_fromstrn(&entry->oid_cur, buf, GIT_OID_HEXSZ) < 0)
	goto fail;
	seek_forward(GIT_OID_HEXSZ + 1);

	ptr = buf;

	/* Seek forward to the end of the signature. */
	while (buf && buf != '\t' && *buf != '\n')
	seek_forward(1);

	if (git_signature__parse(entry->committer, &ptr, buf + 1, NULL, *buf) < 0)
	goto fail;

	if (*buf == '\t') {
	/* We got a message. Read everything till we reach LF. */
	seek_forward(1);
	ptr = buf;

	while (buf && buf != '\n')
	seek_forward(1);

	entry->msg = git__strndup(ptr, buf - ptr);
	GITERR_CHECK_ALLOC(entry->msg);
	} else
	entry->msg = NULL;

	while (buf && buf == '\n' && buf_size > 1)
	seek_forward(1);

	if (git_vector_insert(&log->entries, entry) < 0)
	goto fail;
	}

	return 0;

	#undef seek_forward

	fail:
	if (entry) {
	git__free(entry->committer);
	git__free(entry);
	}
	return -1;
	}

	void git_reflog_free(git_reflog *reflog)
	{
	unsigned int i;
	git_reflog_entry *entry;

	for (i=0; i < reflog->entries.length; i++) {
	entry = git_vector_get(&reflog->entries, i);

	git_signature_free(entry->committer);

	git__free(entry->msg);
	git__free(entry);
	}

	git_vector_free(&reflog->entries);
	git__free(reflog->ref_name);
	git__free(reflog);
	}

	int git_reflog_read(git_reflog *reflog, git_reference ref)
	{
	int error;
	git_buf log_path = GIT_BUF_INIT;
	git_buf log_file = GIT_BUF_INIT;
	git_reflog *log = NULL;

	*reflog = NULL;

	if (reflog_init(&log, ref) < 0)
	return -1;

	error = git_buf_join_n(&log_path, '/', 3,
	ref->owner->path_repository, GIT_REFLOG_DIR, ref->name);

	if (!error)
	error = git_futils_readbuffer(&log_file, log_path.ptr);

	if (!error)
	error = reflog_parse(log, log_file.ptr, log_file.size);

	if (!error)
	*reflog = log;
	else
	git_reflog_free(log);

	git_buf_free(&log_file);
	git_buf_free(&log_path);

	return error;
	}

	int git_reflog_write(git_reference ref, const git_oid oid_old,
	const git_signature committer, const char msg)
	{
	int error;
	char old[GIT_OID_HEXSZ+1];
	char new[GIT_OID_HEXSZ+1];
	git_buf log_path = GIT_BUF_INIT;
	git_reference *r;
	const git_oid *oid;

	if ((error = git_reference_resolve(&r, ref)) < 0)
	return error;

	oid = git_reference_oid(r);
	if (oid == NULL) {
	giterr_set(GITERR_REFERENCE,
	"Failed to write reflog. Cannot resolve reference `%s`", r->name);
	git_reference_free(r);
	return -1;
	}

	git_oid_tostr(new, GIT_OID_HEXSZ+1, oid);

	git_reference_free(r);

	error = git_buf_join_n(&log_path, '/', 3,
	ref->owner->path_repository, GIT_REFLOG_DIR, ref->name);
	if (error < 0)
	goto cleanup;

	if (git_path_exists(log_path.ptr) == false) {
	error = git_futils_mkpath2file(log_path.ptr, GIT_REFLOG_DIR_MODE);
	} else if (git_path_isfile(log_path.ptr) == false) {
	giterr_set(GITERR_REFERENCE,
	"Failed to write reflog. `%s` is directory", log_path.ptr);
	error = -1;
	} else if (oid_old == NULL) {
	giterr_set(GITERR_REFERENCE,
	"Failed to write reflog. Old OID cannot be NULL for existing reference");
	error = -1;
	}
	if (error < 0)
	goto cleanup;

	if (oid_old)
	git_oid_tostr(old, sizeof(old), oid_old);
	else
	p_snprintf(old, sizeof(old), "%0*d", GIT_OID_HEXSZ, 0);

	error = reflog_write(log_path.ptr, old, new, committer, msg);

	cleanup:
	git_buf_free(&log_path);
	return error;
	}

	int git_reflog_rename(git_reference ref, const char new_name)
	{
	int error;
	git_buf old_path = GIT_BUF_INIT;
	git_buf new_path = GIT_BUF_INIT;

	if (!git_buf_join_n(&old_path, '/', 3, ref->owner->path_repository,
	GIT_REFLOG_DIR, ref->name) &&
	!git_buf_join_n(&new_path, '/', 3, ref->owner->path_repository,
	GIT_REFLOG_DIR, new_name))
	error = p_rename(git_buf_cstr(&old_path), git_buf_cstr(&new_path));
	else
	error = -1;

	git_buf_free(&old_path);
	git_buf_free(&new_path);

	return error;
	}

	int git_reflog_delete(git_reference *ref)
	{
	int error;
	git_buf path = GIT_BUF_INIT;

	error = git_buf_join_n(
	&path, '/', 3, ref->owner->path_repository, GIT_REFLOG_DIR, ref->name);

	if (!error && git_path_exists(path.ptr))
	error = p_unlink(path.ptr);

	git_buf_free(&path);

	return error;
	}

	unsigned int git_reflog_entrycount(git_reflog *reflog)
	{
	assert(reflog);
	return reflog->entries.length;
	}

	const git_reflog_entry * git_reflog_entry_byindex(git_reflog *reflog, unsigned int idx)
	{
	assert(reflog);
	return git_vector_get(&reflog->entries, idx);
	}

	const git_oid * git_reflog_entry_oidold(const git_reflog_entry *entry)
	{
	assert(entry);
	return &entry->oid_old;
	}

	const git_oid * git_reflog_entry_oidnew(const git_reflog_entry *entry)
	{
	assert(entry);
	return &entry->oid_cur;
	}

	git_signature * git_reflog_entry_committer(const git_reflog_entry *entry)
	{
	assert(entry);
	return entry->committer;
	}

	char * git_reflog_entry_msg(const git_reflog_entry *entry)
	{
	assert(entry);
	return entry->msg;
	}