git/remote-testsvn.c
Florian Achleitner 68f64ff8b4 Implement a remote helper for svn in C
Enable basic fetching from subversion repositories. When processing
remote URLs starting with testsvn::, git invokes this remote-helper.
It starts svnrdump to extract revisions from the subversion repository
in the 'dump file format', and converts them to a git-fast-import stream
using the functions of vcs-svn/.

Imported refs are created in a private namespace at
refs/svn/<remote-name>/master.  The revision history is imported
linearly (no branch detection) and completely, i.e. from revision 0 to
HEAD.

The 'bidi-import' capability is used. The remote-helper expects data
from fast-import on its stdin. It buffers a batch of 'import' command
lines in a string_list before starting to process them.

Signed-off-by: Florian Achleitner <florian.achleitner.2.6.31@gmail.com>
Acked-by: David Michael Barr <b@rr-dav.id.au>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-10-07 14:10:16 -07:00

177 lines
4.4 KiB
C

#include "cache.h"
#include "remote.h"
#include "strbuf.h"
#include "url.h"
#include "exec_cmd.h"
#include "run-command.h"
#include "vcs-svn/svndump.h"
#include "notes.h"
#include "argv-array.h"
static const char *url;
static const char *private_ref;
static const char *remote_ref = "refs/heads/master";
static int cmd_capabilities(const char *line);
static int cmd_import(const char *line);
static int cmd_list(const char *line);
typedef int (*input_command_handler)(const char *);
struct input_command_entry {
const char *name;
input_command_handler fn;
unsigned char batchable; /* whether the command starts or is part of a batch */
};
static const struct input_command_entry input_command_list[] = {
{ "capabilities", cmd_capabilities, 0 },
{ "import", cmd_import, 1 },
{ "list", cmd_list, 0 },
{ NULL, NULL }
};
static int cmd_capabilities(const char *line)
{
printf("import\n");
printf("bidi-import\n");
printf("refspec %s:%s\n\n", remote_ref, private_ref);
fflush(stdout);
return 0;
}
static void terminate_batch(void)
{
/* terminate a current batch's fast-import stream */
printf("done\n");
fflush(stdout);
}
static int cmd_import(const char *line)
{
int code;
int dumpin_fd;
unsigned int startrev = 0;
struct argv_array svndump_argv = ARGV_ARRAY_INIT;
struct child_process svndump_proc;
memset(&svndump_proc, 0, sizeof(struct child_process));
svndump_proc.out = -1;
argv_array_push(&svndump_argv, "svnrdump");
argv_array_push(&svndump_argv, "dump");
argv_array_push(&svndump_argv, url);
argv_array_pushf(&svndump_argv, "-r%u:HEAD", startrev);
svndump_proc.argv = svndump_argv.argv;
code = start_command(&svndump_proc);
if (code)
die("Unable to start %s, code %d", svndump_proc.argv[0], code);
dumpin_fd = svndump_proc.out;
svndump_init_fd(dumpin_fd, STDIN_FILENO);
svndump_read(url, private_ref);
svndump_deinit();
svndump_reset();
close(dumpin_fd);
code = finish_command(&svndump_proc);
if (code)
warning("%s, returned %d", svndump_proc.argv[0], code);
argv_array_clear(&svndump_argv);
return 0;
}
static int cmd_list(const char *line)
{
printf("? %s\n\n", remote_ref);
fflush(stdout);
return 0;
}
static int do_command(struct strbuf *line)
{
const struct input_command_entry *p = input_command_list;
static struct string_list batchlines = STRING_LIST_INIT_DUP;
static const struct input_command_entry *batch_cmd;
/*
* commands can be grouped together in a batch.
* Batches are ended by \n. If no batch is active the program ends.
* During a batch all lines are buffered and passed to the handler function
* when the batch is terminated.
*/
if (line->len == 0) {
if (batch_cmd) {
struct string_list_item *item;
for_each_string_list_item(item, &batchlines)
batch_cmd->fn(item->string);
terminate_batch();
batch_cmd = NULL;
string_list_clear(&batchlines, 0);
return 0; /* end of the batch, continue reading other commands. */
}
return 1; /* end of command stream, quit */
}
if (batch_cmd) {
if (prefixcmp(batch_cmd->name, line->buf))
die("Active %s batch interrupted by %s", batch_cmd->name, line->buf);
/* buffer batch lines */
string_list_append(&batchlines, line->buf);
return 0;
}
for (p = input_command_list; p->name; p++) {
if (!prefixcmp(line->buf, p->name) && (strlen(p->name) == line->len ||
line->buf[strlen(p->name)] == ' ')) {
if (p->batchable) {
batch_cmd = p;
string_list_append(&batchlines, line->buf);
return 0;
}
return p->fn(line->buf);
}
}
die("Unknown command '%s'\n", line->buf);
return 0;
}
int main(int argc, const char **argv)
{
struct strbuf buf = STRBUF_INIT, url_sb = STRBUF_INIT,
private_ref_sb = STRBUF_INIT;
static struct remote *remote;
const char *url_in;
git_extract_argv0_path(argv[0]);
setup_git_directory();
if (argc < 2 || argc > 3) {
usage("git-remote-svn <remote-name> [<url>]");
return 1;
}
remote = remote_get(argv[1]);
url_in = (argc == 3) ? argv[2] : remote->url[0];
end_url_with_slash(&url_sb, url_in);
url = url_sb.buf;
strbuf_addf(&private_ref_sb, "refs/svn/%s/master", remote->name);
private_ref = private_ref_sb.buf;
while (1) {
if (strbuf_getline(&buf, stdin, '\n') == EOF) {
if (ferror(stdin))
die("Error reading command stream");
else
die("Unexpected end of command stream");
}
if (do_command(&buf))
break;
strbuf_reset(&buf);
}
strbuf_release(&buf);
strbuf_release(&url_sb);
strbuf_release(&private_ref_sb);
return 0;
}