log_ref_setup(): improve robustness against races

diff --git a/mailinfo.c b/mailinfo.c
index 69391aaca13ed121ada52b3f2af8d96af3c8c84b..a489d9d0fbcc37a1198247a8daae4b3104ebe284 100644 (file)
--- a/mailinfo.c
+++ b/mailinfo.c
@@ -54,6 +54,86 @@ static void parse_bogus_from(struct mailinfo *mi, const struct strbuf *line)
        get_sane_name(&mi->name, &mi->name, &mi->email);
 }
 
+static const char *unquote_comment(struct strbuf *outbuf, const char *in)
+{
+       int c;
+       int take_next_litterally = 0;
+
+       strbuf_addch(outbuf, '(');
+
+       while ((c = *in++) != 0) {
+               if (take_next_litterally == 1) {
+                       take_next_litterally = 0;
+               } else {
+                       switch (c) {
+                       case '\\':
+                               take_next_litterally = 1;
+                               continue;
+                       case '(':
+                               in = unquote_comment(outbuf, in);
+                               continue;
+                       case ')':
+                               strbuf_addch(outbuf, ')');
+                               return in;
+                       }
+               }
+
+               strbuf_addch(outbuf, c);
+       }
+
+       return in;
+}
+
+static const char *unquote_quoted_string(struct strbuf *outbuf, const char *in)
+{
+       int c;
+       int take_next_litterally = 0;
+
+       while ((c = *in++) != 0) {
+               if (take_next_litterally == 1) {
+                       take_next_litterally = 0;
+               } else {
+                       switch (c) {
+                       case '\\':
+                               take_next_litterally = 1;
+                               continue;
+                       case '"':
+                               return in;
+                       }
+               }
+
+               strbuf_addch(outbuf, c);
+       }
+
+       return in;
+}
+
+static void unquote_quoted_pair(struct strbuf *line)
+{
+       struct strbuf outbuf;
+       const char *in = line->buf;
+       int c;
+
+       strbuf_init(&outbuf, line->len);
+
+       while ((c = *in++) != 0) {
+               switch (c) {
+               case '"':
+                       in = unquote_quoted_string(&outbuf, in);
+                       continue;
+               case '(':
+                       in = unquote_comment(&outbuf, in);
+                       continue;
+               }
+
+               strbuf_addch(&outbuf, c);
+       }
+
+       strbuf_swap(&outbuf, line);
+       strbuf_release(&outbuf);
+
+}
+
 static void handle_from(struct mailinfo *mi, const struct strbuf *from)
 {
        char *at;
@@ -63,6 +143,8 @@ static void handle_from(struct mailinfo *mi, const struct strbuf *from)
        strbuf_init(&f, from->len);
        strbuf_addbuf(&f, from);
 
+       unquote_quoted_pair(&f);
+
        at = strchr(f.buf, '@');
        if (!at) {
                parse_bogus_from(mi, from);
@@ -500,6 +582,21 @@ static int check_header(struct mailinfo *mi,
        return ret;
 }
 
+/*
+ * Returns 1 if the given line or any line beginning with the given line is an
+ * in-body header (that is, check_header will succeed when passed
+ * mi->s_hdr_data).
+ */
+static int is_inbody_header(const struct mailinfo *mi,
+                           const struct strbuf *line)
+{
+       int i;
+       for (i = 0; header[i]; i++)
+               if (!mi->s_hdr_data[i] && cmp_header(line, header[i]))
+                       return 1;
+       return 0;
+}
+
 static void decode_transfer_encoding(struct mailinfo *mi, struct strbuf *line)
 {
        struct strbuf *ret;
@@ -609,8 +706,34 @@ static int is_scissors_line(const char *line)
                gap * 2 < perforation);
 }
 
+static void flush_inbody_header_accum(struct mailinfo *mi)
+{
+       if (!mi->inbody_header_accum.len)
+               return;
+       if (!check_header(mi, &mi->inbody_header_accum, mi->s_hdr_data, 0))
+               die("BUG: inbody_header_accum, if not empty, must always contain a valid in-body header");
+       strbuf_reset(&mi->inbody_header_accum);
+}
+
 static int check_inbody_header(struct mailinfo *mi, const struct strbuf *line)
 {
+       if (mi->inbody_header_accum.len &&
+           (line->buf[0] == ' ' || line->buf[0] == '\t')) {
+               if (mi->use_scissors && is_scissors_line(line->buf)) {
+                       /*
+                        * This is a scissors line; do not consider this line
+                        * as a header continuation line.
+                        */
+                       flush_inbody_header_accum(mi);
+                       return 0;
+               }
+               strbuf_strip_suffix(&mi->inbody_header_accum, "\n");
+               strbuf_addbuf(&mi->inbody_header_accum, line);
+               return 1;
+       }
+
+       flush_inbody_header_accum(mi);
+
        if (starts_with(line->buf, ">From") && isspace(line->buf[5]))
                return is_format_patch_separator(line->buf + 1, line->len - 1);
        if (starts_with(line->buf, "[PATCH]") && isspace(line->buf[7])) {
@@ -622,7 +745,11 @@ static int check_inbody_header(struct mailinfo *mi, const struct strbuf *line)
                        }
                return 0;
        }
-       return check_header(mi, line, mi->s_hdr_data, 0);
+       if (is_inbody_header(mi, line)) {
+               strbuf_addbuf(&mi->inbody_header_accum, line);
+               return 1;
+       }
+       return 0;
 }
 
 static int handle_commit_msg(struct mailinfo *mi, struct strbuf *line)
@@ -888,6 +1015,8 @@ static void handle_body(struct mailinfo *mi, struct strbuf *line)
                        break;
        } while (!strbuf_getwholeline(line, mi->input, '\n'));
 
+       flush_inbody_header_accum(mi);
+
 handle_body_out:
        strbuf_release(&prev);
 }
@@ -1003,6 +1132,7 @@ void setup_mailinfo(struct mailinfo *mi)
        strbuf_init(&mi->email, 0);
        strbuf_init(&mi->charset, 0);
        strbuf_init(&mi->log_message, 0);
+       strbuf_init(&mi->inbody_header_accum, 0);
        mi->header_stage = 1;
        mi->use_inbody_headers = 1;
        mi->content_top = mi->content;
@@ -1016,6 +1146,7 @@ void clear_mailinfo(struct mailinfo *mi)
        strbuf_release(&mi->name);
        strbuf_release(&mi->email);
        strbuf_release(&mi->charset);
+       strbuf_release(&mi->inbody_header_accum);
        free(mi->message_id);
 
        for (i = 0; mi->p_hdr_data[i]; i++)