Merge remote-tracking branch 'nulltoken/topic/reflog-delete' into development

2 files changed, 222 insertions, 102 deletions

diff --git a/src/reflog.c b/src/reflog.c
index 004ba936d..f841b2174 100644
--- a/src/reflog.c
+++ b/src/reflog.c
@@ -28,66 +28,68 @@ static int reflog_init(git_reflog **reflog, git_reference *ref)
 		return -1;
 	}
 
+	log->owner = git_reference_owner(ref);
 	*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)
+static int serialize_reflog_entry(
+	git_buf *buf,
+	const git_oid *oid_old,
+	const git_oid *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;
+	char raw_old[GIT_OID_HEXSZ+1];
+	char raw_new[GIT_OID_HEXSZ+1];
 
-	assert(log_path && oid_old && oid_new && committer);
+	git_oid_tostr(raw_old, GIT_OID_HEXSZ+1, oid_old);
+	git_oid_tostr(raw_new, GIT_OID_HEXSZ+1, oid_new);
 
-	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_clear(buf);
 
-	git_buf_puts(&log, oid_old);
-	git_buf_putc(&log, ' ');
+	git_buf_puts(buf, raw_old);
+	git_buf_putc(buf, ' ');
+	git_buf_puts(buf, raw_new);
 
-	git_buf_puts(&log, oid_new);
+	git_signature__writebuf(buf, " ", committer);
 
-	git_signature__writebuf(&log, " ", committer);
-	git_buf_truncate(&log, log.size - 1); /* drop LF */
+	/* drop trailing LF */
+	git_buf_rtrim(buf);
 
 	if (msg) {
-		git_buf_putc(&log, '\t');
-		git_buf_puts(&log, msg);
+		git_buf_putc(buf, '\t');
+		git_buf_puts(buf, msg);
 	}
 
-	if (!trailing_newline)
-		git_buf_putc(&log, '\n');
+	git_buf_putc(buf, '\n');
 
-	if (git_buf_oom(&log)) {
-		git_buf_free(&log);
-		return -1;
-	}
+	return git_buf_oom(buf);
+}
 
-	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);
-	}
+static int reflog_entry_new(git_reflog_entry **entry)
+{
+	git_reflog_entry *e;
 
-	git_buf_free(&log);
+	assert(entry);
 
-	return error;
+	e = git__malloc(sizeof(git_reflog_entry));
+	GITERR_CHECK_ALLOC(e);
+
+	memset(e, 0, sizeof(git_reflog_entry));
+
+	*entry = e;
+
+	return 0;
+}
+
+static void reflog_entry_free(git_reflog_entry *entry)
+{
+	git_signature_free(entry->committer);
+
+	git__free(entry->msg);
+	git__free(entry);
 }
 
 static int reflog_parse(git_reflog *log, const char *buf, size_t buf_size)
@@ -105,8 +107,8 @@ static int reflog_parse(git_reflog *log, const char *buf, size_t buf_size)
 	} while (0)
 
 	while (buf_size > GIT_REFLOG_SIZE_MIN) {
-		entry = git__malloc(sizeof(git_reflog_entry));
-		GITERR_CHECK_ALLOC(entry);
+		if (reflog_entry_new(&entry) < 0)
+			return -1;
 
 		entry->committer = git__malloc(sizeof(git_signature));
 		GITERR_CHECK_ALLOC(entry->committer);
@@ -153,10 +155,9 @@ static int reflog_parse(git_reflog *log, const char *buf, size_t buf_size)
 #undef seek_forward
 
 fail:
-	if (entry) {
-		git__free(entry->committer);
-		git__free(entry);
-	}
+	if (entry)
+		reflog_entry_free(entry);
+
 	return -1;
 }
 
@@ -168,10 +169,7 @@ void git_reflog_free(git_reflog *reflog)
 	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);
+		reflog_entry_free(entry);
 	}
 
 	git_vector_free(&reflog->entries);
@@ -179,6 +177,24 @@ void git_reflog_free(git_reflog *reflog)
 	git__free(reflog);
 }
 
+static int retrieve_reflog_path(git_buf *path, git_reference *ref)
+{
+	return git_buf_join_n(path, '/', 3,
+		git_reference_owner(ref)->path_repository, GIT_REFLOG_DIR, ref->name);
+}
+
+int create_new_reflog_file(const char *filepath)
+{
+	int fd;
+
+	if ((fd = p_open(filepath,
+			O_WRONLY | O_CREAT | O_TRUNC,
+			GIT_REFLOG_FILE_MODE)) < 0)
+		return -1;
+
+	return p_close(fd);
+}
+
 int git_reflog_read(git_reflog **reflog, git_reference *ref)
 {
 	int error;
@@ -188,83 +204,136 @@ int git_reflog_read(git_reflog **reflog, git_reference *ref)
 
 	*reflog = NULL;
 
+	assert(reflog && ref);
+
 	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 (retrieve_reflog_path(&log_path, ref) < 0)
+		goto cleanup;
+
+	error = git_futils_readbuffer(&log_file, git_buf_cstr(&log_path));
+	if (error < 0 && error != GIT_ENOTFOUND)
+		goto cleanup;
+
+	if ((error == GIT_ENOTFOUND) &&
+		((error = create_new_reflog_file(git_buf_cstr(&log_path))) < 0))
+		goto cleanup;
 
-	if (!error)
-		error = git_futils_readbuffer(&log_file, log_path.ptr);
+	if ((error = reflog_parse(log,
+		git_buf_cstr(&log_file), git_buf_len(&log_file))) < 0)
+		goto cleanup;
 
-	if (!error)
-		error = reflog_parse(log, log_file.ptr, log_file.size);
+	*reflog = log;
+	goto success;
 
-	if (!error)
-		*reflog = log;
-	else
-		git_reflog_free(log);
+cleanup:
+	git_reflog_free(log);
 
+success:
 	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 git_reflog_write(git_reflog *reflog)
 {
-	int error;
-	char old[GIT_OID_HEXSZ+1];
-	char new[GIT_OID_HEXSZ+1];
+	int error = -1;
+	unsigned int i;
+	git_reflog_entry *entry;
 	git_buf log_path = GIT_BUF_INIT;
-	git_reference *r;
-	const git_oid *oid;
+	git_buf log = GIT_BUF_INIT;
+	git_filebuf fbuf = GIT_FILEBUF_INIT;
+
+	assert(reflog);
 
-	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);
+	if (git_buf_join_n(&log_path, '/', 3,
+		git_repository_path(reflog->owner), GIT_REFLOG_DIR, reflog->ref_name) < 0)
 		return -1;
+
+	if (!git_path_isfile(git_buf_cstr(&log_path))) {
+		giterr_set(GITERR_INVALID,
+			"Log file for reference '%s' doesn't exist.", reflog->ref_name);
+		goto cleanup;
+	}
+
+	if ((error = git_filebuf_open(&fbuf, git_buf_cstr(&log_path), 0)) < 0)
+		goto cleanup;
+
+	git_vector_foreach(&reflog->entries, i, entry) {
+		if (serialize_reflog_entry(&log, &(entry->oid_old), &(entry->oid_cur), entry->committer, entry->msg) < 0)
+			goto cleanup;
+
+		if ((error = git_filebuf_write(&fbuf, log.ptr, log.size)) < 0)
+			goto cleanup;
 	}
+	
+	error = git_filebuf_commit(&fbuf, GIT_REFLOG_FILE_MODE);
+	goto success;
+
+cleanup:
+	git_filebuf_cleanup(&fbuf);
+
+success:
+	git_buf_free(&log);
+	git_buf_free(&log_path);
+	return error;
+}
 
-	git_oid_tostr(new, GIT_OID_HEXSZ+1, oid);
+int git_reflog_append(git_reflog *reflog, const git_oid *new_oid,
+				const git_signature *committer, const char *msg)
+{
+	int count;
+	git_reflog_entry *entry;
+	const char *newline;
 
-	git_reference_free(r);
+	assert(reflog && new_oid && committer);
 
-	error = git_buf_join_n(&log_path, '/', 3,
-		ref->owner->path_repository, GIT_REFLOG_DIR, ref->name);
-	if (error < 0)
+	if (reflog_entry_new(&entry) < 0)
+		return -1;
+
+	if ((entry->committer = git_signature_dup(committer)) == NULL)
 		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 (msg != NULL) {
+		if ((entry->msg = git__strdup(msg)) == NULL)
+			goto cleanup;
+
+		newline = strchr(msg, '\n');
+
+		if (newline) {
+			if (newline[1] != '\0') {
+				giterr_set(GITERR_INVALID, "Reflog message cannot contain newline");
+				goto cleanup;
+			}
+
+			entry->msg[newline - msg] = '\0';
+		}
 	}
-	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);
+	count = git_reflog_entrycount(reflog);
+
+	if (count == 0)
+		git_oid_fromstr(&entry->oid_old, GIT_OID_HEX_ZERO);
+	else {
+		const git_reflog_entry *previous;
 
-	error = reflog_write(log_path.ptr, old, new, committer, msg);
+		previous = git_reflog_entry_byindex(reflog, count -1);
+		git_oid_cpy(&entry->oid_old, &previous->oid_cur);
+	}
+
+	git_oid_cpy(&entry->oid_cur, new_oid);
+
+	if (git_vector_insert(&reflog->entries, entry) < 0)
+		goto cleanup;
+
+	return 0;
 
 cleanup:
-	git_buf_free(&log_path);
-	return error;
+	reflog_entry_free(entry);
+	return -1;
 }
 
 int git_reflog_rename(git_reference *ref, const char *new_name)
@@ -276,7 +345,7 @@ int git_reflog_rename(git_reference *ref, const char *new_name)
 
 	assert(ref && new_name);
 
-	if (git_buf_joinpath(&temp_path, ref->owner->path_repository, GIT_REFLOG_DIR) < 0)
+	if (git_buf_joinpath(&temp_path, git_reference_owner(ref)->path_repository, GIT_REFLOG_DIR) < 0)
 		return -1;
 
 	if (git_buf_joinpath(&old_path, git_buf_cstr(&temp_path), ref->name) < 0)
@@ -324,8 +393,7 @@ 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);
+	error = retrieve_reflog_path(&path, ref);
 
 	if (!error && git_path_exists(path.ptr))
 		error = p_unlink(path.ptr);
@@ -370,3 +438,52 @@ char * git_reflog_entry_msg(const git_reflog_entry *entry)
 	assert(entry);
 	return entry->msg;
 }
+
+int git_reflog_entry_drop(
+	git_reflog *reflog,
+	unsigned int idx,
+	int rewrite_previous_entry)
+{
+	unsigned int entrycount;
+	git_reflog_entry *entry, *previous;
+
+	assert(reflog);
+
+	entrycount = git_reflog_entrycount(reflog);
+
+	if (idx >= entrycount)
+		return GIT_ENOTFOUND;
+
+	entry = git_vector_get(&reflog->entries, idx);
+	reflog_entry_free(entry);
+
+	if (git_vector_remove(&reflog->entries, idx) < 0)
+		return -1;
+
+	if (!rewrite_previous_entry)
+		return 0;
+
+	/* No need to rewrite anything when removing the first entry */
+	if (idx == 0)
+		return 0;
+
+	/* There are no more entries in the log */
+	if (entrycount == 1)
+		return 0;
+
+	entry = (git_reflog_entry *)git_reflog_entry_byindex(reflog, idx - 1);
+
+	/* If the last entry has just been removed... */
+	if (idx == entrycount - 1) {
+		/* ...clear the oid_old member of the "new" last entry */
+		if (git_oid_fromstr(&entry->oid_old, GIT_OID_HEX_ZERO) < 0)
+			return -1;
+		
+		return 0;
+	}
+
+	previous = (git_reflog_entry *)git_reflog_entry_byindex(reflog, idx);
+	git_oid_cpy(&entry->oid_old, &previous->oid_cur);
+
+	return 0;
+}
diff --git a/src/reflog.h b/src/reflog.h
index 33cf0776c..3bbdf6e10 100644
--- a/src/reflog.h
+++ b/src/reflog.h
@@ -17,6 +17,8 @@
 
 #define GIT_REFLOG_SIZE_MIN (2*GIT_OID_HEXSZ+2+17)
 
+#define GIT_OID_HEX_ZERO "0000000000000000000000000000000000000000"
+
 struct git_reflog_entry {
 	git_oid oid_old;
 	git_oid oid_cur;
@@ -28,6 +30,7 @@ struct git_reflog_entry {
 
 struct git_reflog {
 	char *ref_name;
+	git_repository *owner;
 	git_vector entries;
 };