diff --color: color blank-at-eof
[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index f91f256c56e5e4be0b3f162695e1d35e63124569..2b285b8ce90faed3218d5af1524283fc65c9540d 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -489,8 +489,10 @@ typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
 
 struct emit_callback {
        struct xdiff_emit_state xm;
-       int nparents, color_diff;
+       int color_diff;
        unsigned ws_rule;
+       int blank_at_eof;
+       int lno_in_preimage;
        sane_truncate_fn truncate;
        const char **label_path;
        struct diff_words_data *diff_words;
@@ -547,11 +549,16 @@ static void emit_add_line(const char *reset, struct emit_callback *ecbdata, cons
 
        if (!*ws)
                emit_line(ecbdata->file, set, reset, line, len);
+       else if ((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
+                ecbdata->blank_at_eof &&
+                (ecbdata->blank_at_eof <= ecbdata->lno_in_preimage) &&
+                ws_blank_line(line + 1, len - 1, ecbdata->ws_rule))
+               /* Blank line at EOF */
+               emit_line(ecbdata->file, ws, reset, line, len);
        else {
                /* Emit just the prefix, then the rest. */
-               emit_line(ecbdata->file, set, reset, line, ecbdata->nparents);
-               ws_check_emit(line + ecbdata->nparents,
-                             len - ecbdata->nparents, ecbdata->ws_rule,
+               emit_line(ecbdata->file, set, reset, line, 1);
+               ws_check_emit(line + 1, len - 1, ecbdata->ws_rule,
                              ecbdata->file, set, reset, ws);
        }
 }
@@ -574,10 +581,16 @@ static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, u
        return allot - l;
 }
 
+static int find_preimage_lno(const char *line)
+{
+       char *p = strchr(line, '-');
+       if (!p)
+               return 0; /* should not happen */
+       return strtol(p+1, NULL, 10);
+}
+
 static void fn_out_consume(void *priv, char *line, unsigned long len)
 {
-       int i;
-       int color;
        struct emit_callback *ecbdata = priv;
        const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
        const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
@@ -598,14 +611,9 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
                ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
        }
 
-       /* This is not really necessary for now because
-        * this codepath only deals with two-way diffs.
-        */
-       for (i = 0; i < len && line[i] == '@'; i++)
-               ;
-       if (2 <= i && i < len && line[i] == ' ') {
-               ecbdata->nparents = i - 1;
+       if (line[0] == '@') {
                len = sane_truncate_line(ecbdata, line, len);
+               ecbdata->lno_in_preimage = find_preimage_lno(line);
                emit_line(ecbdata->file,
                          diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
                          reset, line, len);
@@ -614,15 +622,11 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
                return;
        }
 
-       if (len < ecbdata->nparents) {
+       if (len < 1) {
                emit_line(ecbdata->file, reset, reset, line, len);
                return;
        }
 
-       color = DIFF_PLAIN;
-       if (ecbdata->diff_words && ecbdata->nparents != 1)
-               /* fall back to normal diff */
-               free_diff_words_data(ecbdata);
        if (ecbdata->diff_words) {
                if (line[0] == '-') {
                        diff_words_append(line, len,
@@ -641,17 +645,13 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
                emit_line(ecbdata->file, plain, reset, line, len);
                return;
        }
-       for (i = 0; i < ecbdata->nparents && len; i++) {
-               if (line[i] == '-')
-                       color = DIFF_FILE_OLD;
-               else if (line[i] == '+')
-                       color = DIFF_FILE_NEW;
-       }
 
-       if (color != DIFF_FILE_NEW) {
-               emit_line(ecbdata->file,
-                         diff_get_color(ecbdata->color_diff, color),
-                         reset, line, len);
+       if (line[0] != '+') {
+               const char *color =
+                       diff_get_color(ecbdata->color_diff,
+                                      line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
+               ecbdata->lno_in_preimage++;
+               emit_line(ecbdata->file, color, reset, line, len);
                return;
        }
        emit_add_line(reset, ecbdata, line, len);
@@ -1163,7 +1163,6 @@ struct checkdiff_t {
        struct diff_options *o;
        unsigned ws_rule;
        unsigned status;
-       int trailing_blanks_start;
 };
 
 static int is_conflict_marker(const char *line, unsigned long len)
@@ -1207,10 +1206,6 @@ static void checkdiff_consume(void *priv, char *line, unsigned long len)
        if (line[0] == '+') {
                unsigned bad;
                data->lineno++;
-               if (!ws_blank_line(line + 1, len - 1, data->ws_rule))
-                       data->trailing_blanks_start = 0;
-               else if (!data->trailing_blanks_start)
-                       data->trailing_blanks_start = data->lineno;
                if (is_conflict_marker(line + 1, len - 1)) {
                        data->status |= 1;
                        fprintf(data->o->file,
@@ -1230,14 +1225,12 @@ static void checkdiff_consume(void *priv, char *line, unsigned long len)
                              data->o->file, set, reset, ws);
        } else if (line[0] == ' ') {
                data->lineno++;
-               data->trailing_blanks_start = 0;
        } else if (line[0] == '@') {
                char *plus = strchr(line, '+');
                if (plus)
                        data->lineno = strtol(plus, NULL, 10) - 1;
                else
                        die("invalid diff");
-               data->trailing_blanks_start = 0;
        }
 }
 
@@ -1451,6 +1444,44 @@ static const struct funcname_pattern_entry *diff_funcname_pattern(struct diff_fi
        return NULL;
 }
 
+static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
+{
+       char *ptr = mf->ptr;
+       long size = mf->size;
+       int cnt = 0;
+
+       if (!size)
+               return cnt;
+       ptr += size - 1; /* pointing at the very end */
+       if (*ptr != '\n')
+               ; /* incomplete line */
+       else
+               ptr--; /* skip the last LF */
+       while (mf->ptr < ptr) {
+               char *prev_eol;
+               for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
+                       if (*prev_eol == '\n')
+                               break;
+               if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
+                       break;
+               cnt++;
+               ptr = prev_eol - 1;
+       }
+       return cnt;
+}
+
+static int adds_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2, unsigned ws_rule)
+{
+       int l1, l2, at;
+       l1 = count_trailing_blank(mf1, ws_rule);
+       l2 = count_trailing_blank(mf2, ws_rule);
+       if (l2 <= l1)
+               return 0;
+       /* starting where? */
+       at = count_lines(mf1->ptr, mf1->size);
+       return (at - l1) + 1; /* the line number counts from 1 */
+}
+
 static void builtin_diff(const char *name_a,
                         const char *name_b,
                         struct diff_filespec *one,
@@ -1540,6 +1571,9 @@ static void builtin_diff(const char *name_a,
                ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
                ecbdata.found_changesp = &o->found_changes;
                ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
+               if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
+                       ecbdata.blank_at_eof =
+                               adds_blank_at_eof(&mf1, &mf2, ecbdata.ws_rule);
                ecbdata.file = o->file;
                xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
                xecfg.ctxlen = o->context;
@@ -1664,11 +1698,16 @@ static void builtin_checkdiff(const char *name_a, const char *name_b,
                ecb.priv = &data;
                xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 
-               if ((data.ws_rule & WS_TRAILING_SPACE) &&
-                   data.trailing_blanks_start) {
-                       fprintf(o->file, "%s:%d: ends with blank lines.\n",
-                               data.filename, data.trailing_blanks_start);
-                       data.status = 1; /* report errors */
+               if (data.ws_rule & WS_BLANK_AT_EOF) {
+                       int blank_at_eof = adds_blank_at_eof(&mf1, &mf2, data.ws_rule);
+                       if (blank_at_eof) {
+                               static char *err;
+                               if (!err)
+                                       err = whitespace_error_string(WS_BLANK_AT_EOF);
+                               fprintf(o->file, "%s:%d: %s.\n",
+                                       data.filename, blank_at_eof, err);
+                               data.status = 1; /* report errors */
+                       }
                }
        }
  free_and_return:
@@ -2096,16 +2135,86 @@ static const char *external_diff_attr(const char *name)
        return NULL;
 }
 
+static int similarity_index(struct diff_filepair *p)
+{
+       return p->score * 100 / MAX_SCORE;
+}
+
+static void fill_metainfo(struct strbuf *msg,
+                         const char *name,
+                         const char *other,
+                         struct diff_filespec *one,
+                         struct diff_filespec *two,
+                         struct diff_options *o,
+                         struct diff_filepair *p)
+{
+       strbuf_init(msg, PATH_MAX * 2 + 300);
+       switch (p->status) {
+       case DIFF_STATUS_COPIED:
+               strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
+               strbuf_addstr(msg, "\ncopy from ");
+               quote_c_style(name, msg, NULL, 0);
+               strbuf_addstr(msg, "\ncopy to ");
+               quote_c_style(other, msg, NULL, 0);
+               strbuf_addch(msg, '\n');
+               break;
+       case DIFF_STATUS_RENAMED:
+               strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
+               strbuf_addstr(msg, "\nrename from ");
+               quote_c_style(name, msg, NULL, 0);
+               strbuf_addstr(msg, "\nrename to ");
+               quote_c_style(other, msg, NULL, 0);
+               strbuf_addch(msg, '\n');
+               break;
+       case DIFF_STATUS_MODIFIED:
+               if (p->score) {
+                       strbuf_addf(msg, "dissimilarity index %d%%\n",
+                                   similarity_index(p));
+                       break;
+               }
+               /* fallthru */
+       default:
+               /* nothing */
+               ;
+       }
+       if (one && two && hashcmp(one->sha1, two->sha1)) {
+               int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
+
+               if (DIFF_OPT_TST(o, BINARY)) {
+                       mmfile_t mf;
+                       if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
+                           (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
+                               abbrev = 40;
+               }
+               strbuf_addf(msg, "index %.*s..%.*s",
+                           abbrev, sha1_to_hex(one->sha1),
+                           abbrev, sha1_to_hex(two->sha1));
+               if (one->mode == two->mode)
+                       strbuf_addf(msg, " %06o", one->mode);
+               strbuf_addch(msg, '\n');
+       }
+       if (msg->len)
+               strbuf_setlen(msg, msg->len - 1);
+}
+
 static void run_diff_cmd(const char *pgm,
                         const char *name,
                         const char *other,
                         const char *attr_path,
                         struct diff_filespec *one,
                         struct diff_filespec *two,
-                        const char *xfrm_msg,
+                        struct strbuf *msg,
                         struct diff_options *o,
-                        int complete_rewrite)
+                        struct diff_filepair *p)
 {
+       const char *xfrm_msg = NULL;
+       int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
+
+       if (msg) {
+               fill_metainfo(msg, name, other, one, two, o, p);
+               xfrm_msg = msg->len ? msg->buf : NULL;
+       }
+
        if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
                pgm = NULL;
        else {
@@ -2145,11 +2254,6 @@ static void diff_fill_sha1_info(struct diff_filespec *one)
                hashclr(one->sha1);
 }
 
-static int similarity_index(struct diff_filepair *p)
-{
-       return p->score * 100 / MAX_SCORE;
-}
-
 static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
 {
        /* Strip the prefix but do not molest /dev/null and absolute paths */
@@ -2163,13 +2267,11 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 {
        const char *pgm = external_diff();
        struct strbuf msg;
-       char *xfrm_msg;
        struct diff_filespec *one = p->one;
        struct diff_filespec *two = p->two;
        const char *name;
        const char *other;
        const char *attr_path;
-       int complete_rewrite = 0;
 
        name  = p->one->path;
        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
@@ -2179,83 +2281,34 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 
        if (DIFF_PAIR_UNMERGED(p)) {
                run_diff_cmd(pgm, name, NULL, attr_path,
-                            NULL, NULL, NULL, o, 0);
+                            NULL, NULL, NULL, o, p);
                return;
        }
 
        diff_fill_sha1_info(one);
        diff_fill_sha1_info(two);
 
-       strbuf_init(&msg, PATH_MAX * 2 + 300);
-       switch (p->status) {
-       case DIFF_STATUS_COPIED:
-               strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
-               strbuf_addstr(&msg, "\ncopy from ");
-               quote_c_style(name, &msg, NULL, 0);
-               strbuf_addstr(&msg, "\ncopy to ");
-               quote_c_style(other, &msg, NULL, 0);
-               strbuf_addch(&msg, '\n');
-               break;
-       case DIFF_STATUS_RENAMED:
-               strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
-               strbuf_addstr(&msg, "\nrename from ");
-               quote_c_style(name, &msg, NULL, 0);
-               strbuf_addstr(&msg, "\nrename to ");
-               quote_c_style(other, &msg, NULL, 0);
-               strbuf_addch(&msg, '\n');
-               break;
-       case DIFF_STATUS_MODIFIED:
-               if (p->score) {
-                       strbuf_addf(&msg, "dissimilarity index %d%%\n",
-                                       similarity_index(p));
-                       complete_rewrite = 1;
-                       break;
-               }
-               /* fallthru */
-       default:
-               /* nothing */
-               ;
-       }
-
-       if (hashcmp(one->sha1, two->sha1)) {
-               int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
-
-               if (DIFF_OPT_TST(o, BINARY)) {
-                       mmfile_t mf;
-                       if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
-                           (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
-                               abbrev = 40;
-               }
-               strbuf_addf(&msg, "index %.*s..%.*s",
-                               abbrev, sha1_to_hex(one->sha1),
-                               abbrev, sha1_to_hex(two->sha1));
-               if (one->mode == two->mode)
-                       strbuf_addf(&msg, " %06o", one->mode);
-               strbuf_addch(&msg, '\n');
-       }
-
-       if (msg.len)
-               strbuf_setlen(&msg, msg.len - 1);
-       xfrm_msg = msg.len ? msg.buf : NULL;
-
        if (!pgm &&
            DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
            (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
-               /* a filepair that changes between file and symlink
+               /*
+                * a filepair that changes between file and symlink
                 * needs to be split into deletion and creation.
                 */
                struct diff_filespec *null = alloc_filespec(two->path);
                run_diff_cmd(NULL, name, other, attr_path,
-                            one, null, xfrm_msg, o, 0);
+                            one, null, &msg, o, p);
                free(null);
+               strbuf_release(&msg);
+
                null = alloc_filespec(one->path);
                run_diff_cmd(NULL, name, other, attr_path,
-                            null, two, xfrm_msg, o, 0);
+                            null, two, &msg, o, p);
                free(null);
        }
        else
                run_diff_cmd(pgm, name, other, attr_path,
-                            one, two, xfrm_msg, o, complete_rewrite);
+                            one, two, &msg, o, p);
 
        strbuf_release(&msg);
 }