git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCH 5/6] Add infrastructure to write revisions in fast-export format

From
Ramkumar Ramachandra <artagnon@gmail.com>
Date
Jun 10, 2010, 13:09 UTC
Message-ID
<1276175389-6185-6-git-send-email-artagnon@gmail.com>
In-Reply-To
<1276175389-6185-1-git-send-email-artagnon@gmail.com>
From: David Barr <david.barr@cordelta.com>

repo_tree maintains the exporter's state and provides a facility to to call fast_export, which then writes objects to stdout suitable for consumption by git-fast-import.

Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
---
 vcs-svn/fast_export.c |   74 +++++++++++
 vcs-svn/fast_export.h |   14 ++
 vcs-svn/repo_tree.c   |  335 +++++++++++++++++++++++++++++++++++++++++++++++++
 vcs-svn/repo_tree.h   |   26 ++++
 4 files changed, 449 insertions(+), 0 deletions(-)
 create mode 100644 vcs-svn/fast_export.c
 create mode 100644 vcs-svn/fast_export.h
 create mode 100644 vcs-svn/repo_tree.c
 create mode 100644 vcs-svn/repo_tree.h
diff --git a/vcs-svn/fast_export.c b/vcs-svn/fast_export.c
new file mode 100644
index 0000000..0fe6672
--- /dev/null
+++ b/vcs-svn/fast_export.c
@@ -0,0 +1,74 @@
+/*
+ * Licensed under a two-clause BSD-style license.
+ * See LICENSE for details.
+ */
+
+#include "git-compat-util.h"
+
+#include "fast_export.h"
+#include "line_buffer.h"
+#include "repo_tree.h"
+#include "string_pool.h"
+
+#define MAX_GITSVN_LINE_LEN 4096
+
+static uint32_t first_commit_done;
+
+void fast_export_delete(uint32_t depth, uint32_t *path)
+{
+	putchar('D');
+	putchar(' ');
+	pool_print_seq(depth, path, '/', stdout);
+	putchar('\n');
+}
+
+void fast_export_modify(uint32_t depth, uint32_t *path, uint32_t mode,
+						uint32_t mark)
+{
+	printf("M %06o :%d ", mode, mark);
+	pool_print_seq(depth, path, '/', stdout);
+	putchar('\n');
+}
+
+static char gitsvnline[MAX_GITSVN_LINE_LEN];
+void fast_export_commit(uint32_t revision, uint32_t author, char *log,
+			uint32_t uuid, uint32_t url,
+			unsigned long timestamp)
+{
+	if (!log)
+		log = "";
+	if (~uuid && ~url) {
+		snprintf(gitsvnline, MAX_GITSVN_LINE_LEN, "\n\ngit-svn-id: %s@%d %s\n",
+				 pool_fetch(url), revision, pool_fetch(uuid));
+	} else {
+		*gitsvnline = '\0';
+	}
+	printf("commit refs/heads/master\n");
+	printf("committer %s <%s@%s> %ld +0000\n",
+		   ~author ? pool_fetch(author) : "nobody",
+		   ~author ? pool_fetch(author) : "nobody",
+		   ~uuid ? pool_fetch(uuid) : "local", timestamp);
+	printf("data %zd\n%s%s\n",
+		   strlen(log) + strlen(gitsvnline), log, gitsvnline);
+	if (!first_commit_done) {
+		if (revision > 1)
+			printf("from refs/heads/master^0\n");
+		first_commit_done = 1;
+	}
+	repo_diff(revision - 1, revision);
+	fputc('\n', stdout);
+
+	printf("progress Imported commit %d.\n\n", revision);
+}
+
+void fast_export_blob(uint32_t mode, uint32_t mark, uint32_t len)
+{
+	if (mode == REPO_MODE_LNK) {
+		/* svn symlink blobs start with "link " */
+		buffer_skip_bytes(5);
+		len -= 5;
+	}
+	printf("blob\nmark :%d\ndata %d\n", mark, len);
+	buffer_copy_bytes(len);
+	fputc('\n', stdout);
+}
diff --git a/vcs-svn/fast_export.h b/vcs-svn/fast_export.h
new file mode 100644
index 0000000..47e8f56
--- /dev/null
+++ b/vcs-svn/fast_export.h
@@ -0,0 +1,14 @@
+#ifndef FAST_EXPORT_H_
+#define FAST_EXPORT_H_
+
+#include <stdint.h>
+#include <time.h>
+
+void fast_export_delete(uint32_t depth, uint32_t *path);
+void fast_export_modify(uint32_t depth, uint32_t *path, uint32_t mode,
+			uint32_t mark);
+void fast_export_commit(uint32_t revision, uint32_t author, char *log,
+			uint32_t uuid, uint32_t url, unsigned long timestamp);
+void fast_export_blob(uint32_t mode, uint32_t mark, uint32_t len);
+
+#endif
diff --git a/vcs-svn/repo_tree.c b/vcs-svn/repo_tree.c
new file mode 100644
index 0000000..6565779
--- /dev/null
+++ b/vcs-svn/repo_tree.c
@@ -0,0 +1,335 @@
+/*
+ * Licensed under a two-clause BSD-style license.
+ * See LICENSE for details.
+ */
+
+#include "git-compat-util.h"
+
+#include "string_pool.h"
+#include "repo_tree.h"
+#include "obj_pool.h"
+#include "fast_export.h"
+
+#include "trp.h"
+
+struct repo_dirent {
+	uint32_t name_offset;
+	struct trp_node children;
+	uint32_t mode;
+	uint32_t content_offset;
+};
+
+struct repo_dir {
+	struct trp_root entries;
+};
+
+struct repo_commit {
+	uint32_t root_dir_offset;
+};
+
+/* Generate memory pools for commit, dir and dirent */
+obj_pool_gen(commit, struct repo_commit, 4096);
+obj_pool_gen(dir, struct repo_dir, 4096);
+obj_pool_gen(dirent, struct repo_dirent, 4096);
+
+static int repo_dirent_name_cmp(const void *a, const void *b);
+
+/* Build a Treap from the node_s structure (a trp_node w/ offset) */
+trp_gen(static, dirent_, struct repo_dirent, children, dirent, repo_dirent_name_cmp);
+
+static uint32_t active_commit;
+static uint32_t _mark;
+
+uint32_t next_blob_mark(void)
+{
+	return _mark++;
+}
+
+static struct repo_dir *repo_commit_root_dir(struct repo_commit *commit)
+{
+	return dir_pointer(commit->root_dir_offset);
+}
+
+static struct repo_dirent *repo_first_dirent(struct repo_dir *dir)
+{
+	return dirent_first(&dir->entries);
+}
+
+static int repo_dirent_name_cmp(const void *a, const void *b)
+{
+	const struct repo_dirent *dirent1 = a, *dirent2 = b;
+	uint32_t a_offset = dirent1->name_offset;
+	uint32_t b_offset = dirent2->name_offset;
+	return (a_offset > b_offset) - (a_offset < b_offset);
+}
+
+static int repo_dirent_is_dir(struct repo_dirent *dirent)
+{
+	return dirent != NULL && dirent->mode == REPO_MODE_DIR;
+}
+
+static struct repo_dir *repo_dir_from_dirent(struct repo_dirent *dirent)
+{
+	if (!repo_dirent_is_dir(dirent))
+		return NULL;
+	return dir_pointer(dirent->content_offset);
+}
+
+static struct repo_dir *repo_clone_dir(struct repo_dir *orig_dir)
+{
+	uint32_t orig_o, new_o;
+	orig_o = dir_offset(orig_dir);
+	if (orig_o >= dir_pool.committed)
+		return orig_dir;
+	new_o = dir_alloc(1);
+	orig_dir = dir_pointer(orig_o);
+	*dir_pointer(new_o) = *orig_dir;
+	return dir_pointer(new_o);
+}
+
+static struct repo_dirent *repo_read_dirent(uint32_t revision, uint32_t *path)
+{
+	uint32_t name = 0;
+	struct repo_dirent *key = dirent_pointer(dirent_alloc(1));
+	struct repo_dir *dir = NULL;
+	struct repo_dirent *dirent = NULL;
+	dir = repo_commit_root_dir(commit_pointer(revision));
+	while (~(name = *path++)) {
+		key->name_offset = name;
+		dirent = dirent_search(&dir->entries, key);
+		if (dirent == NULL || !repo_dirent_is_dir(dirent))
+			break;
+		dir = repo_dir_from_dirent(dirent);
+	}
+	dirent_free(1);
+	return dirent;
+}
+
+static void
+repo_write_dirent(uint32_t *path, uint32_t mode, uint32_t content_offset,
+		  uint32_t del)
+{
+	uint32_t name, revision, dir_o = ~0, parent_dir_o = ~0;
+	struct repo_dir *dir;
+	struct repo_dirent *key;
+	struct repo_dirent *dirent = NULL;
+	revision = active_commit;
+	dir = repo_commit_root_dir(commit_pointer(revision));
+	dir = repo_clone_dir(dir);
+	commit_pointer(revision)->root_dir_offset = dir_offset(dir);
+	while (~(name = *path++)) {
+		parent_dir_o = dir_offset(dir);
+
+		key = dirent_pointer(dirent_alloc(1));
+		key->name_offset = name;
+
+		dirent = dirent_search(&dir->entries, key);
+		if (dirent == NULL)
+			dirent = key;
+		else
+			dirent_free(1);
+
+		if (dirent == key) {
+			dirent->mode = REPO_MODE_DIR;
+			dirent->content_offset = 0;
+			dirent_insert(&dir->entries, dirent);
+		}
+
+
+		if (dirent_offset(dirent) < dirent_pool.committed) {
+			dir_o = repo_dirent_is_dir(dirent) ? dirent->content_offset : ~0;
+			dirent_remove(&dir->entries, dirent);
+			dirent = dirent_pointer(dirent_alloc(1));
+			dirent->name_offset = name;
+			dirent->mode = REPO_MODE_DIR;
+			dirent->content_offset = dir_o;
+			dirent_insert(&dir->entries, dirent);
+		}
+
+		dir = repo_dir_from_dirent(dirent);
+		dir = repo_clone_dir(dir);
+		dirent->content_offset = dir_offset(dir);
+	}
+	if (dirent == NULL)
+		return;
+	dirent->mode = mode;
+	dirent->content_offset = content_offset;
+	if (del && ~parent_dir_o)
+		dirent_remove(&dir_pointer(parent_dir_o)->entries, dirent);
+}
+
+uint32_t repo_copy(uint32_t revision, uint32_t *src, uint32_t *dst)
+{
+	uint32_t mode = 0, content_offset = 0;
+	struct repo_dirent *src_dirent;
+	src_dirent = repo_read_dirent(revision, src);
+	if (src_dirent != NULL) {
+		mode = src_dirent->mode;
+		content_offset = src_dirent->content_offset;
+		repo_write_dirent(dst, mode, content_offset, 0);
+	}
+	return mode;
+}
+
+void repo_add(uint32_t *path, uint32_t mode, uint32_t blob_mark)
+{
+	repo_write_dirent(path, mode, blob_mark, 0);
+}
+
+uint32_t repo_replace(uint32_t *path, uint32_t blob_mark)
+{
+	uint32_t mode = 0;
+	struct repo_dirent *src_dirent;
+	src_dirent = repo_read_dirent(active_commit, path);
+	if (src_dirent != NULL) {
+		mode = src_dirent->mode;
+		repo_write_dirent(path, mode, blob_mark, 0);
+	}
+	return mode;
+}
+
+void repo_modify(uint32_t *path, uint32_t mode, uint32_t blob_mark)
+{
+	struct repo_dirent *src_dirent;
+	src_dirent = repo_read_dirent(active_commit, path);
+	if (src_dirent != NULL && blob_mark == 0) {
+		blob_mark = src_dirent->content_offset;
+	}
+	repo_write_dirent(path, mode, blob_mark, 0);
+}
+
+void repo_delete(uint32_t *path)
+{
+	repo_write_dirent(path, 0, 0, 1);
+}
+
+static void repo_git_add_r(uint32_t depth, uint32_t *path, struct repo_dir *dir);
+
+static void repo_git_add(uint32_t depth, uint32_t *path, struct repo_dirent *dirent)
+{
+	if (repo_dirent_is_dir(dirent)) {
+		repo_git_add_r(depth, path, repo_dir_from_dirent(dirent));
+	} else {
+		fast_export_modify(depth, path, dirent->mode, dirent->content_offset);
+	}
+}
+
+static void repo_git_add_r(uint32_t depth, uint32_t *path, struct repo_dir *dir)
+{
+	struct repo_dirent *de = repo_first_dirent(dir);
+	while (de) {
+		path[depth] = de->name_offset;
+		repo_git_add(depth + 1, path, de);
+		de = dirent_next(&dir->entries, de);
+	}
+}
+
+static void repo_diff_r(uint32_t depth, uint32_t *path, struct repo_dir *dir1,
+			struct repo_dir *dir2)
+{
+	struct repo_dirent *de1, *de2;
+	de1 = repo_first_dirent(dir1);
+	de2 = repo_first_dirent(dir2);
+
+	while (de1 && de2) {
+		if (de1->name_offset < de2->name_offset) {
+			path[depth] = de1->name_offset;
+			fast_export_delete(depth + 1, path);
+			de1 = dirent_next(&dir1->entries, de1);
+			continue;
+		} else if (de1->name_offset > de2->name_offset) {
+			path[depth] = de2->name_offset;
+			repo_git_add(depth + 1, path, de2);
+			de2 = dirent_next(&dir2->entries, de2);
+			continue;
+		}
+		path[depth] = de1->name_offset;
+		if (de1->mode != de2->mode ||
+		    de1->content_offset != de2->content_offset) {
+			if (repo_dirent_is_dir(de1) && repo_dirent_is_dir(de2)) {
+				repo_diff_r(depth + 1, path,
+					    repo_dir_from_dirent(de1),
+					    repo_dir_from_dirent(de2));
+			} else {
+				if (repo_dirent_is_dir(de1) != repo_dirent_is_dir(de2)) {
+					fast_export_delete(depth + 1, path);
+				}
+				repo_git_add(depth + 1, path, de2);
+			}
+		}
+		de1 = dirent_next(&dir1->entries, de1);
+		de2 = dirent_next(&dir2->entries, de2);
+	}
+	while (de1) {
+		path[depth] = de1->name_offset;
+		fast_export_delete(depth + 1, path);
+		de1 = dirent_next(&dir1->entries, de1);
+	}
+	while (de2) {
+		path[depth] = de2->name_offset;
+		repo_git_add(depth + 1, path, de2);
+		de2 = dirent_next(&dir2->entries, de2);
+	}
+}
+
+static uint32_t path_stack[REPO_MAX_PATH_DEPTH];
+
+void repo_diff(uint32_t r1, uint32_t r2)
+{
+	repo_diff_r(0,
+		    path_stack,
+		    repo_commit_root_dir(commit_pointer(r1)),
+		    repo_commit_root_dir(commit_pointer(r2)));
+}
+
+void repo_commit(uint32_t revision, uint32_t author, char *log, uint32_t uuid,
+		 uint32_t url, unsigned long timestamp)
+{
+	fast_export_commit(revision, author, log, uuid, url, timestamp);
+	pool_commit();
+	dirent_commit();
+	dir_commit();
+	commit_commit();
+	active_commit = commit_alloc(1);
+	commit_pointer(active_commit)->root_dir_offset =
+		commit_pointer(active_commit - 1)->root_dir_offset;
+}
+
+static void mark_init(void)
+{
+	uint32_t i;
+	_mark = 0;
+	for (i = 0; i < dirent_pool.size; i++)
+		if (!repo_dirent_is_dir(dirent_pointer(i)) &&
+		    dirent_pointer(i)->content_offset > _mark)
+			_mark = dirent_pointer(i)->content_offset;
+	_mark++;
+}
+
+void repo_init() {
+	pool_init();
+	commit_init();
+	dir_init();
+	dirent_init();
+	mark_init();
+	if (commit_pool.size == 0) {
+		/* Create empty tree for commit 0. */
+		commit_alloc(1);
+		commit_pointer(0)->root_dir_offset = dir_alloc(1);
+		dir_pointer(0)->entries.trp_root = ~0;
+		dir_commit();
+		commit_commit();
+	}
+	/* Preallocate next commit, ready for changes. */
+	active_commit = commit_alloc(1);
+	commit_pointer(active_commit)->root_dir_offset =
+		commit_pointer(active_commit - 1)->root_dir_offset;
+}
+
+void repo_reset(void)
+{
+	pool_reset();
+	commit_reset();
+	dir_reset();
+	dirent_reset();
+}
diff --git a/vcs-svn/repo_tree.h b/vcs-svn/repo_tree.h
new file mode 100644
index 0000000..5476175
--- /dev/null
+++ b/vcs-svn/repo_tree.h
@@ -0,0 +1,26 @@
+#ifndef REPO_TREE_H_
+#define REPO_TREE_H_
+
+#include "git-compat-util.h"
+
+#define REPO_MODE_DIR 0040000
+#define REPO_MODE_BLB 0100644
+#define REPO_MODE_EXE 0100755
+#define REPO_MODE_LNK 0120000
+
+#define REPO_MAX_PATH_LEN 4096
+#define REPO_MAX_PATH_DEPTH 1000
+
+uint32_t next_blob_mark(void);
+uint32_t repo_copy(uint32_t revision, uint32_t *src, uint32_t *dst);
+void repo_add(uint32_t *path, uint32_t mode, uint32_t blob_mark);
+uint32_t repo_replace(uint32_t *path, uint32_t blob_mark);
+void repo_modify(uint32_t *path, uint32_t mode, uint32_t blob_mark);
+void repo_delete(uint32_t *path);
+void repo_commit(uint32_t revision, uint32_t author, char *log, uint32_t uuid,
+		 uint32_t url, long unsigned timestamp);
+void repo_diff(uint32_t r1, uint32_t r2);
+void repo_init(void);
+void repo_reset(void);
+
+#endif
-- 
1.7.1
Previous: Ramkumar RamachandraNext: Ramkumar Ramachandra
Message 14 of 19 in “Another attempt to get the SVN exporter merged”
  1. 0/6 Another attempt to get the SVN exporter mergedRamkumar Ramachandra, Jun 10, 2010
  2. 1/6 Add memory pool libraryRamkumar Ramachandra, Jun 10, 2010
  3. Jonathan NiederJun 12, 2010
  4. Ramkumar RamachandraJun 14, 2010
  5. Andreas EricssonJun 14, 2010
  6. 2/6 Add cpp macro implementation of treapsRamkumar Ramachandra, Jun 10, 2010
  7. 3/6 Add library for string-specific memory poolRamkumar Ramachandra, Jun 10, 2010
  8. Junio C HamanoJun 11, 2010
  9. Ramkumar RamachandraJun 14, 2010
  10. Junio C HamanoJun 14, 2010
  11. Ramkumar RamachandraJun 14, 2010
  12. David Michael BarrJun 14, 2010
  13. 4/6 Add stream helper libraryRamkumar Ramachandra, Jun 10, 2010
  14. 5/6 Add infrastructure to write revisions in fast-export formatRamkumar Ramachandra, Jun 10, 2010
  15. 6/6 Add SVN dump parserRamkumar Ramachandra, Jun 10, 2010
  16. Ramkumar RamachandraJun 10, 2010
  17. Jonathan NiederJun 12, 2010
  18. Ramkumar RamachandraJun 14, 2010
  19. Ramkumar RamachandraJun 10, 2010

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.