Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@xxxxxxxxx>
---
backup-log.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++++++
backup-log.h | 21 ++++++-
2 files changed, 193 insertions(+), 1 deletion(-)
diff --git a/backup-log.c b/backup-log.c
index c1e805b09e..49f2ce68fe 100644
--- a/backup-log.c
+++ b/backup-log.c
@@ -44,3 +44,176 @@ int bkl_write(const char *path, struct strbuf *new_log)
rollback_lock_file(&lk);
return ret;
}
+
+int bkl_parse_entry(struct strbuf *sb, struct bkl_entry *re)
+{
+ char *email_end, *message;
+ const char *p = sb->buf;
+
+ /* old SP new SP name <email> SP time TAB msg LF */
+ if (!sb->len || sb->buf[sb->len - 1] != '\n' ||
+ parse_oid_hex(p, &re->old_oid, &p) || *p++ != ' ' ||
+ parse_oid_hex(p, &re->new_oid, &p) || *p++ != ' ' ||
+ !(email_end = strchr(p, '>')) ||
+ email_end[1] != ' ')
+ return -1; /* corrupt? */
+ re->email = p;
+ re->timestamp = parse_timestamp(email_end + 2, &message, 10);
+ if (!re->timestamp ||
+ !message || message[0] != ' ' ||
+ (message[1] != '+' && message[1] != '-') ||
+ !isdigit(message[2]) || !isdigit(message[3]) ||
+ !isdigit(message[4]) || !isdigit(message[5]))
+ return -1; /* corrupt? */
+ email_end[1] = '\0';
+ re->tz = strtol(message + 1, NULL, 10);
+ if (message[6] != '\t')
+ message += 6;
+ else
+ message += 7;
+ sb->buf[sb->len - 1] = '\0'; /* no LF */
+ re->path = message;
+ return 0;
+}
+
+static char *find_beginning_of_line(char *bob, char *scan)
+{
+ while (bob < scan && *(--scan) != '\n')
+ ; /* keep scanning backwards */
+ /*
+ * Return either beginning of the buffer, or LF at the end of
+ * the previous line.
+ */
+ return scan;
+}
+
+int bkl_parse_file_reverse(const char *path,
+ int (*parse)(struct strbuf *line, void *data),
+ void *data)
+{
+ struct strbuf sb = STRBUF_INIT;
+ FILE *logfp;
+ long pos;
+ int ret = 0, at_tail = 1;
+
+ logfp = fopen(path, "r");
+ if (!logfp) {
+ if (errno == ENOENT || errno == ENOTDIR)
+ return 0;
+ return -1;
+ }
+
+ /* Jump to the end */
+ if (fseek(logfp, 0, SEEK_END) < 0)
+ ret = error_errno(_("cannot seek back in %s"), path);
+ pos = ftell(logfp);
+ while (!ret && 0 < pos) {
+ int cnt;
+ size_t nread;
+ char buf[BUFSIZ];
+ char *endp, *scanp;
+
+ /* Fill next block from the end */
+ cnt = (sizeof(buf) < pos) ? sizeof(buf) : pos;
+ if (fseek(logfp, pos - cnt, SEEK_SET)) {
+ ret = error_errno(_("cannot seek back in %s"), path);
+ break;
+ }
+ nread = fread(buf, cnt, 1, logfp);
+ if (nread != 1) {
+ ret = error_errno(_("cannot read %d bytes from %s"),
+ cnt, path);
+ break;
+ }
+ pos -= cnt;
+
+ scanp = endp = buf + cnt;
+ if (at_tail && scanp[-1] == '\n')
+ /* Looking at the final LF at the end of the file */
+ scanp--;
+ at_tail = 0;
+
+ while (buf < scanp) {
+ /*
+ * terminating LF of the previous line, or the beginning
+ * of the buffer.
+ */
+ char *bp;
+
+ bp = find_beginning_of_line(buf, scanp);
+
+ if (*bp == '\n') {
+ /*
+ * The newline is the end of the previous line,
+ * so we know we have complete line starting
+ * at (bp + 1). Prefix it onto any prior data
+ * we collected for the line and process it.
+ */
+ strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));
+ scanp = bp;
+ endp = bp + 1;
+ ret = parse(&sb, data);
+ strbuf_reset(&sb);
+ if (ret)
+ break;
+ } else if (!pos) {
+ /*
+ * We are at the start of the buffer, and the
+ * start of the file; there is no previous
+ * line, and we have everything for this one.
+ * Process it, and we can end the loop.
+ */
+ strbuf_splice(&sb, 0, 0, buf, endp - buf);
+ ret = parse(&sb, data);
+ strbuf_reset(&sb);
+ break;
+ }
+
+ if (bp == buf) {
+ /*
+ * We are at the start of the buffer, and there
+ * is more file to read backwards. Which means
+ * we are in the middle of a line. Note that we
+ * may get here even if *bp was a newline; that
+ * just means we are at the exact end of the
+ * previous line, rather than some spot in the
+ * middle.
+ *
+ * Save away what we have to be combined with
+ * the data from the next read.
+ */
+ strbuf_splice(&sb, 0, 0, buf, endp - buf);
+ break;
+ }
+ }
+
+ }
+ if (!ret && sb.len)
+ BUG("reverse reflog parser had leftover data");
+
+ fclose(logfp);
+ strbuf_release(&sb);
+ return ret;
+}
+
+int bkl_parse_file(const char *path,
+ int (*parse)(struct strbuf *line, void *data),
+ void *data)
+{
+ struct strbuf sb = STRBUF_INIT;
+ FILE *logfp;
+ int ret = 0;
+
+ logfp = fopen(path, "r");
+ if (!logfp) {
+ if (errno == ENOENT || errno == ENOTDIR)
+ return 0;
+ return -1;
+ }
+
+ while (!ret && !strbuf_getwholeline(&sb, logfp, '\n'))
+ ret = parse(&sb, data);
+ fclose(logfp);
+ strbuf_release(&sb);
+ return ret;
+}
diff --git a/backup-log.h b/backup-log.h
index 5e475d6f35..c9de9c687c 100644
--- a/backup-log.h
+++ b/backup-log.h
@@ -1,13 +1,32 @@
#ifndef __BACKUP_LOG_H__
#define __BACKUP_LOG_H__
-struct object_id;
+#include "cache.h"
+
struct strbuf;
+struct bkl_entry
+{
+ struct object_id old_oid;
+ struct object_id new_oid;
+ const char *email;
+ timestamp_t timestamp;
+ int tz;
+ const char *path;
+};
+
void bkl_append(struct strbuf *output, const char *path,
const struct object_id *from,
const struct object_id *to);
int bkl_write(const char *path, struct strbuf *new_log);
+int bkl_parse_entry(struct strbuf *sb, struct bkl_entry *re);
+int bkl_parse_file_reverse(const char *path,
+ int (*parse)(struct strbuf *line, void *data),
+ void *data);
+int bkl_parse_file(const char *path,
+ int (*parse)(struct strbuf *line, void *data),
+ void *data);
+
#endif
--
2.20.0.rc2.486.g9832c05c3d
