Introduce usagef() that takes a printf-style format

diff --git a/combine-diff.c b/combine-diff.c
index 60d03676bbd0dba7be79c7098d7cae553962ca98..5b63af1eeb71907f23117bc552fa7a4019f09722 100644 (file)
--- a/combine-diff.c
+++ b/combine-diff.c
@@ -80,6 +80,7 @@ struct lline {
 /* Lines surviving in the merge result */
 struct sline {
        struct lline *lost_head, **lost_tail;
+       struct lline *next_lost;
        char *bol;
        int len;
        /* bit 0 up to (N-1) are on if the parent has this line (i.e.
@@ -121,18 +122,12 @@ static void append_lost(struct sline *sline, int n, const char *line, int len)
 
        /* Check to see if we can squash things */
        if (sline->lost_head) {
-               struct lline *last_one = NULL;
-               /* We cannot squash it with earlier one */
-               for (lline = sline->lost_head;
-                    lline;
-                    lline = lline->next)
-                       if (lline->parent_map & this_mask)
-                               last_one = lline;
-               lline = last_one ? last_one->next : sline->lost_head;
+               lline = sline->next_lost;
                while (lline) {
                        if (lline->len == len &&
                            !memcmp(lline->line, line, len)) {
                                lline->parent_map |= this_mask;
+                               sline->next_lost = lline->next;
                                return;
                        }
                        lline = lline->next;
@@ -147,6 +142,7 @@ static void append_lost(struct sline *sline, int n, const char *line, int len)
        lline->line[len] = 0;
        *sline->lost_tail = lline;
        sline->lost_tail = &lline->next;
+       sline->next_lost = NULL;
 }
 
 struct combine_diff_state {
@@ -168,25 +164,28 @@ static void consume_line(void *state_, char *line, unsigned long len)
                                      &state->nb, &state->nn))
                        return;
                state->lno = state->nb;
-               if (!state->nb)
-                       /* @@ -1,2 +0,0 @@ to remove the
-                        * first two lines...
-                        */
-                       state->nb = 1;
-               if (state->nn == 0)
+               if (state->nn == 0) {
                        /* @@ -X,Y +N,0 @@ removed Y lines
                         * that would have come *after* line N
                         * in the result.  Our lost buckets hang
                         * to the line after the removed lines,
+                        *
+                        * Note that this is correct even when N == 0,
+                        * in which case the hunk removes the first
+                        * line in the file.
                         */
                        state->lost_bucket = &state->sline[state->nb];
-               else
+                       if (!state->nb)
+                               state->nb = 1;
+               } else {
                        state->lost_bucket = &state->sline[state->nb-1];
+               }
                if (!state->sline[state->nb-1].p_lno)
                        state->sline[state->nb-1].p_lno =
                                xcalloc(state->num_parent,
                                        sizeof(unsigned long));
                state->sline[state->nb-1].p_lno[state->n] = state->ob;
+               state->lost_bucket->next_lost = state->lost_bucket->lost_head;
                return;
        }
        if (!state->lost_bucket)
@@ -746,7 +745,7 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
 
                        done = read_in_full(fd, result, len);
                        if (done < 0)
-                               die("read error '%s'", elem->path);
+                               die_errno("read error '%s'", elem->path);
                        else if (done < len)
                                die("early EOF '%s'", elem->path);