Intial indexer code

include/git2.h

@@ -60,5 +60,6 @@
 #include "git2/net.h"
 #include "git2/transport.h"
 #include "git2/status.h"
+#include "git2/indexer.h"
 
 #endif

include/git2/indexer.h

@@ -0,0 +1,15 @@
+#ifndef _INCLUDE_git_indexer_h__
+#define _INCLUDE_git_indexer_h__
+
+typedef struct git_pack_indexer {
+	struct pack_file *pack;
+	git_vector objects;
+	git_vector deltas;
+	struct stat st;
+} git_pack_indexer;
+
+GIT_EXTERN(int) git_pack_indexer_new(git_pack_indexer **out, const char *packname);
+GIT_EXTERN(void) git_pack_indexer_free(git_pack_indexer *idx)
+
+
+#endif

src/indexer.c

@@ -0,0 +1,133 @@
+/*
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2,
+ * as published by the Free Software Foundation.
+ *
+ * In addition to the permissions in the GNU General Public License,
+ * the authors give you unlimited permission to link the compiled
+ * version of this file into combinations with other programs,
+ * and to distribute those combinations without any restriction
+ * coming from the use of this file.  (The General Public License
+ * restrictions do apply in other respects; for example, they cover
+ * modification of the file, and distribution when not linked into
+ * a combined executable.)
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include "common.h"
+#include "pack.h"
+#include "posix.h"
+
+static int parse_header(git_pack_indexer *idx)
+{
+	struct pack_header hdr;
+	int error;
+
+	/* Verify we recognize this pack file format. */
+	if ((error = p_read(idx->pack->pack_fd, &hdr, sizeof(hdr))) < GIT_SUCCESS)
+		goto cleanup;
+
+	if (hdr.hdr_signature != htonl(PACK_SIGNATURE)) {
+		error = git__throw(GIT_EOBJCORRUPTED, "Wrong pack signature");
+		goto cleanup;
+	}
+
+	if (!pack_version_ok(hdr.hdr_version)) {
+		error = git__throw(GIT_EOBJCORRUPTED, "Wrong pack version");
+		goto cleanup;
+	}
+
+	/*
+	 * FIXME: At this point we have no idea how many of the are
+	 * deltas, so assume all objects are both until we get a better
+	 * idea 
+	 */
+	error = git_vector_init(&idx->objects, hdr.hdr_entries, NULL /* FIXME: probably need something */);
+	if (error < GIT_SUCCESS)
+		goto cleanup;
+
+	error = git_vector_init(&idx->deltas, hdr.hdr_entries, NULL /* FIXME: probably need something */);
+	if (error < GIT_SUCCESS)
+		goto cleanup;
+
+	return GIT_SUCCESS;
+
+cleanup:
+	git_vector_free(&idx->objects);
+	git_vector_free(&idx->deltas);
+
+	return error;
+}
+
+int git_pack_indexer_new(git_pack_indexer **out, const char *packname)
+{
+	struct git_pack_indexer *idx;
+	unsigned int namelen;
+	int ret, error;
+
+	idx = git__malloc(sizeof(struct git_pack_indexer));
+	if (idx == NULL)
+		return GIT_ENOMEM;
+
+	memset(idx, 0x0, sizeof(*idx));
+
+	namelen = strlen(packname);
+	idx->pack = git__malloc(sizeof(struct pack_file) + namelen + 1);
+	if (idx->pack == NULL)
+		goto cleanup;
+
+	memset(idx->pack, 0x0, sizeof(struct pack_file));
+	memcpy(idx->pack->pack_name, packname, namelen);
+
+	ret = p_stat(packname, &idx->st);
+	if (ret < 0) {
+		if (errno == ENOENT)
+			error = git__throw(GIT_ENOTFOUND, "Failed to stat packfile. File not found");
+		else
+			error = git__throw(GIT_EOSERR, "Failed to stat packfile.");
+
+		goto cleanup;
+	}
+
+	ret = p_open(idx->pack->pack_name, O_RDONLY);
+	if (ret < 0) {
+		error = git__throw(GIT_EOSERR, "Failed to open packfile");
+		goto cleanup;
+	}
+
+	idx->pack->pack_fd = ret;
+
+	error = parse_header(idx);
+	if (error < GIT_SUCCESS) {
+		error = git__rethrow(error, "Failed to parse packfile header");
+		goto cleanup;
+	}
+
+	*out = idx;
+
+	return GIT_SUCCESS;
+
+cleanup:
+	free(idx->pack);
+	free(idx);
+
+	return error;
+}
+
+void git_pack_indexer_free(git_pack_indexer *idx)
+{
+	p_close(idx->pack->pack_fd);
+	git_vector_free(&idx->objects);
+	git_vector_free(&idx->deltas);
+	free(idx->pack);
+	free(idx);
+}