4:14 p.m.
From: "Richard W.M. Jones" <rjones(a)redhat.com>
---
src/dbdump.c | 181 ++++++++++++++++++++++++++++++++++-------------------------
1 file changed, 103 insertions(+), 78 deletions(-)
diff --git a/src/dbdump.c b/src/dbdump.c
index 201fa6e..6c9d7a7 100644
--- a/src/dbdump.c
+++ b/src/dbdump.c
@@ -39,111 +39,136 @@
#if defined(DB_DUMP)
+static void read_db_dump_line (guestfs_h *g, void *datav, const char *line, size_t len);
static unsigned char *convert_hex_to_binary (guestfs_h *g, const char *hex, size_t
hexlen, size_t *binlen_rtn);
+struct cb_data {
+ guestfs___db_dump_callback callback;
+ void *opaque;
+ enum { reading_header,
+ reading_key, reading_value,
+ reading_finished,
+ reading_failed } state;
+ unsigned char *key;
+ size_t keylen;
+};
+
/* This helper function is specialized to just reading the hash-format
* output from db_dump/db4_dump. It's just enough to support the RPM
- * database format. Note that the filename must not contain any shell
- * characters (this is guaranteed by the caller).
+ * database format.
*/
int
guestfs___read_db_dump (guestfs_h *g,
const char *dumpfile, void *opaque,
guestfs___db_dump_callback callback)
{
-#define cmd_len (strlen (dumpfile) + 64)
- char cmd[cmd_len];
- FILE *pp = NULL;
- char *line = NULL;
- size_t len = 0;
- ssize_t linelen;
- unsigned char *key = NULL, *value = NULL;
- size_t keylen, valuelen;
- int ret = -1;
-
- snprintf (cmd, cmd_len, DB_DUMP " -k '%s'", dumpfile);
-
- debug (g, "read_db_dump command: %s", cmd);
-
- pp = popen (cmd, "r");
- if (pp == NULL) {
- perrorf (g, "popen: %s", cmd);
- goto out;
- }
+ struct cb_data data;
+ struct command *cmd;
+ int r;
- /* Ignore everything to end-of-header marker. */
- while ((linelen = getline (&line, &len, pp)) != -1) {
- if (STRPREFIX (line, "HEADER=END"))
- break;
- }
+ data.callback = callback;
+ data.opaque = opaque;
+ data.state = reading_header;
+ data.key = NULL;
+
+ cmd = guestfs___new_command (g);
+ guestfs___cmd_add_arg (cmd, DB_DUMP);
+ guestfs___cmd_add_arg (cmd, "-k");
+ guestfs___cmd_add_arg (cmd, dumpfile);
+ guestfs___cmd_set_stdout_callback (cmd, read_db_dump_line, &data, 0);
+
+ r = guestfs___cmd_run (cmd);
+ guestfs___cmd_close (cmd);
+ free (data.key);
- if (linelen == -1) {
- error (g, _("unexpected end of output from db_dump command before end of
header"));
- goto out;
+ if (r == -1)
+ return -1;
+ if (!WIFEXITED (r) || WEXITSTATUS (r) != 0) {
+ error (g, _("%s: command failed"), DB_DUMP);
+ return -1;
+ }
+ if (data.state != reading_finished) {
+ error (g, _("%s: unexpected error or end of output"), DB_DUMP);
+ return -1;
}
- /* Now read the key, value pairs. They are prefixed with a space and
- * printed as hex strings, so convert those strings to binary. Pass
- * the strings up to the callback function.
- */
- while ((linelen = getline (&line, &len, pp)) != -1) {
- if (STRPREFIX (line, "DATA=END"))
- break;
-
- if (linelen < 1 || line[0] != ' ') {
- error (g, _("unexpected line from db_dump command, no space prefix"));
- goto out;
- }
+ return 0;
+}
- if ((key = convert_hex_to_binary (g, &line[1], linelen-1,
- &keylen)) == NULL)
- goto out;
+static void
+read_db_dump_line (guestfs_h *g, void *datav, const char *line, size_t len)
+{
+ struct cb_data *data = datav;
+ unsigned char *value;
+ size_t valuelen;
- if ((linelen = getline (&line, &len, pp)) == -1)
- break;
+ switch (data->state) {
+ case reading_finished:
+ case reading_failed:
+ return;
- if (linelen < 1 || line[0] != ' ') {
- error (g, _("unexpected line from db_dump command, no space prefix"));
- goto out;
+ case reading_header:
+ /* Ignore everything to end-of-header marker. */
+ if (STRPREFIX (line, "HEADER=END"))
+ data->state = reading_key;
+ return;
+
+ /* Read the key, value pairs using a state machine. They are
+ * prefixed with a space and printed as hex strings, so convert
+ * those strings to binary. Pass the strings up to the callback
+ * function.
+ */
+ case reading_key:
+ if (STRPREFIX (line, "DATA=END")) {
+ data->state = reading_finished;
+ return;
}
- if ((value = convert_hex_to_binary (g, &line[1], linelen-1,
- &valuelen)) == NULL)
- goto out;
+ if (len < 1 || line[0] != ' ') {
+ debug (g, _("unexpected line from db_dump command, no space prefix"));
+ data->state = reading_failed;
+ return;
+ }
- if (callback (g, key, keylen, value, valuelen, opaque) == -1)
- goto out;
+ data->key = convert_hex_to_binary (g, &line[1], len-1, &data->keylen);
+ if (data->key == NULL) {
+ data->state = reading_failed;
+ return;
+ }
- free (key);
- free (value);
- key = value = NULL;
- }
+ data->state = reading_value;
+ return;
- if (linelen == -1) {
- error (g, _("unexpected end of output from db_dump command before end of
data"));
- goto out;
- }
+ case reading_value:
+ if (len < 1 || line[0] != ' ') {
+ debug (g, _("unexpected line from db_dump command, no space prefix"));
+ data->state = reading_failed;
+ return;
+ }
- /* Catch errors from the db_dump command. */
- if (pclose (pp) != 0) {
- perrorf (g, "pclose: %s", cmd);
- pp = NULL;
- goto out;
- }
- pp = NULL;
+ value = convert_hex_to_binary (g, &line[1], len-1, &valuelen);
+ if (value == NULL) {
+ data->state = reading_failed;
+ return;
+ }
- ret = 0;
+ if (data->callback (g, data->key, data->keylen,
+ value, valuelen, data->opaque) == -1) {
+ data->state = reading_failed;
+ return;
+ }
- out:
- if (pp)
- pclose (pp);
+ free (data->key);
+ data->key = NULL;
+ free (value);
+ value = NULL;
- free (line);
- free (key);
- free (value);
+ data->state = reading_key;
+ return;
- return ret;
-#undef cmd_len
+ default:
+ abort ();
+ }
}
static int
--
1.7.11.4