From: Junio C Hamano <gitster@pobox.com>
Date: Wed, 27 Dec 2017 19:16:24 +0000 (-0800)
Subject: Merge branch 'rs/strbuf-read-once-reset-length'
X-Git-Tag: v2.16.0-rc0~31
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/a13e45f1e7e6fc02d4e10e0589578a77e84f3ffb?hp=-c

Merge branch 'rs/strbuf-read-once-reset-length'

Leakfix.

* rs/strbuf-read-once-reset-length:
strbuf: release memory on read error in strbuf_read_once()
---

a13e45f1e7e6fc02d4e10e0589578a77e84f3ffb
diff --combined strbuf.c
index 323c49ceb3,0809bca256..ac5a7ab62d
--- a/strbuf.c
+++ b/strbuf.c
@@@ -204,6 -204,13 +204,6 @@@ void strbuf_addbuf(struct strbuf *sb, c
  	strbuf_setlen(sb, sb->len + sb2->len);
  }
  
 -void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
 -{
 -	strbuf_grow(sb, len);
 -	memcpy(sb->buf + sb->len, sb->buf + pos, len);
 -	strbuf_setlen(sb, sb->len + len);
 -}
 -
  void strbuf_addchars(struct strbuf *sb, int c, size_t n)
  {
  	strbuf_grow(sb, n);
@@@ -386,12 -393,15 +386,15 @@@ ssize_t strbuf_read(struct strbuf *sb, 
  
  ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
  {
+ 	size_t oldalloc = sb->alloc;
  	ssize_t cnt;
  
  	strbuf_grow(sb, hint ? hint : 8192);
  	cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
  	if (cnt > 0)
  		strbuf_setlen(sb, sb->len + cnt);
+ 	else if (oldalloc == 0)
+ 		strbuf_release(sb);
  	return cnt;
  }
  
@@@ -442,17 -452,6 +445,17 @@@ int strbuf_getcwd(struct strbuf *sb
  			strbuf_setlen(sb, strlen(sb->buf));
  			return 0;
  		}
 +
 +		/*
 +		 * If getcwd(3) is implemented as a syscall that falls
 +		 * back to a regular lookup using readdir(3) etc. then
 +		 * we may be able to avoid EACCES by providing enough
 +		 * space to the syscall as it's not necessarily bound
 +		 * to the same restrictions as the fallback.
 +		 */
 +		if (errno == EACCES && guessed_len < PATH_MAX)
 +			continue;
 +
  		if (errno != ERANGE)
  			break;
  	}
@@@ -476,7 -475,6 +479,7 @@@ int strbuf_getwholeline(struct strbuf *
  	/* Translate slopbuf to NULL, as we cannot call realloc on it */
  	if (!sb->alloc)
  		sb->buf = NULL;
 +	errno = 0;
  	r = getdelim(&sb->buf, &sb->alloc, term, fp);
  
  	if (r > 0) {
@@@ -779,47 -777,14 +782,47 @@@ char *xstrfmt(const char *fmt, ...
  	return ret;
  }
  
 -void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm)
 +void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm,
 +		     int tz_offset, int suppress_tz_name)
  {
 +	struct strbuf munged_fmt = STRBUF_INIT;
  	size_t hint = 128;
  	size_t len;
  
  	if (!*fmt)
  		return;
  
 +	/*
 +	 * There is no portable way to pass timezone information to
 +	 * strftime, so we handle %z and %Z here.
 +	 */
 +	for (;;) {
 +		const char *percent = strchrnul(fmt, '%');
 +		strbuf_add(&munged_fmt, fmt, percent - fmt);
 +		if (!*percent)
 +			break;
 +		fmt = percent + 1;
 +		switch (*fmt) {
 +		case '%':
 +			strbuf_addstr(&munged_fmt, "%%");
 +			fmt++;
 +			break;
 +		case 'z':
 +			strbuf_addf(&munged_fmt, "%+05d", tz_offset);
 +			fmt++;
 +			break;
 +		case 'Z':
 +			if (suppress_tz_name) {
 +				fmt++;
 +				break;
 +			}
 +			/* FALLTHROUGH */
 +		default:
 +			strbuf_addch(&munged_fmt, '%');
 +		}
 +	}
 +	fmt = munged_fmt.buf;
 +
  	strbuf_grow(sb, hint);
  	len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
  
@@@ -831,16 -796,17 +834,16 @@@
  		 * output contains at least one character, and then drop the extra
  		 * character before returning.
  		 */
 -		struct strbuf munged_fmt = STRBUF_INIT;
 -		strbuf_addf(&munged_fmt, "%s ", fmt);
 +		strbuf_addch(&munged_fmt, ' ');
  		while (!len) {
  			hint *= 2;
  			strbuf_grow(sb, hint);
  			len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
  				       munged_fmt.buf, tm);
  		}
 -		strbuf_release(&munged_fmt);
  		len--; /* drop munged space */
  	}
 +	strbuf_release(&munged_fmt);
  	strbuf_setlen(sb, sb->len + len);
  }