git-remote-mediawiki: add a .perlcriticrc file
[gitweb.git] / combine-diff.c
index 21fd00ff6156f7eb7af6b74dd569325af3f37820..6dc06093d3c1eb6f3ab7a9cc79f0f192e16dc617 100644 (file)
@@ -5,6 +5,7 @@
 #include "diffcore.h"
 #include "quote.h"
 #include "xdiff-interface.h"
+#include "xdiff/xmacros.h"
 #include "log-tree.h"
 #include "refs.h"
 #include "userdiff.h"
@@ -73,16 +74,24 @@ static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr,
 
 /* Lines lost from parent */
 struct lline {
-       struct lline *next;
+       struct lline *next, *prev;
        int len;
        unsigned long parent_map;
        char line[FLEX_ARRAY];
 };
 
+/* Lines lost from current parent (before coalescing) */
+struct plost {
+       struct lline *lost_head, *lost_tail;
+       int len;
+};
+
 /* Lines surviving in the merge result */
 struct sline {
-       struct lline *lost_head, **lost_tail;
-       struct lline *next_lost;
+       /* Accumulated and coalesced lost lines */
+       struct lline *lost;
+       int lenlost;
+       struct plost plost;
        char *bol;
        int len;
        /* bit 0 up to (N-1) are on if the parent has this line (i.e.
@@ -94,6 +103,172 @@ struct sline {
        unsigned long *p_lno;
 };
 
+static int match_string_spaces(const char *line1, int len1,
+                              const char *line2, int len2,
+                              long flags)
+{
+       if (flags & XDF_WHITESPACE_FLAGS) {
+               for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
+               for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
+       }
+
+       if (!(flags & (XDF_IGNORE_WHITESPACE | XDF_IGNORE_WHITESPACE_CHANGE)))
+               return (len1 == len2 && !memcmp(line1, line2, len1));
+
+       while (len1 > 0 && len2 > 0) {
+               len1--;
+               len2--;
+               if (XDL_ISSPACE(line1[len1]) || XDL_ISSPACE(line2[len2])) {
+                       if ((flags & XDF_IGNORE_WHITESPACE_CHANGE) &&
+                           (!XDL_ISSPACE(line1[len1]) || !XDL_ISSPACE(line2[len2])))
+                               return 0;
+
+                       for (; len1 > 0 && XDL_ISSPACE(line1[len1]); len1--);
+                       for (; len2 > 0 && XDL_ISSPACE(line2[len2]); len2--);
+               }
+               if (line1[len1] != line2[len2])
+                       return 0;
+       }
+
+       if (flags & XDF_IGNORE_WHITESPACE) {
+               /* Consume remaining spaces */
+               for (; len1 > 0 && XDL_ISSPACE(line1[len1 - 1]); len1--);
+               for (; len2 > 0 && XDL_ISSPACE(line2[len2 - 1]); len2--);
+       }
+
+       /* We matched full line1 and line2 */
+       if (!len1 && !len2)
+               return 1;
+
+       return 0;
+}
+
+enum coalesce_direction { MATCH, BASE, NEW };
+
+/* Coalesce new lines into base by finding LCS */
+static struct lline *coalesce_lines(struct lline *base, int *lenbase,
+                                   struct lline *new, int lennew,
+                                   unsigned long parent, long flags)
+{
+       int **lcs;
+       enum coalesce_direction **directions;
+       struct lline *baseend, *newend = NULL;
+       int i, j, origbaselen = *lenbase;
+
+       if (new == NULL)
+               return base;
+
+       if (base == NULL) {
+               *lenbase = lennew;
+               return new;
+       }
+
+       /*
+        * Coalesce new lines into base by finding the LCS
+        * - Create the table to run dynamic programing
+        * - Compute the LCS
+        * - Then reverse read the direction structure:
+        *   - If we have MATCH, assign parent to base flag, and consume
+        *   both baseend and newend
+        *   - Else if we have BASE, consume baseend
+        *   - Else if we have NEW, insert newend lline into base and
+        *   consume newend
+        */
+       lcs = xcalloc(origbaselen + 1, sizeof(int*));
+       directions = xcalloc(origbaselen + 1, sizeof(enum coalesce_direction*));
+       for (i = 0; i < origbaselen + 1; i++) {
+               lcs[i] = xcalloc(lennew + 1, sizeof(int));
+               directions[i] = xcalloc(lennew + 1, sizeof(enum coalesce_direction));
+               directions[i][0] = BASE;
+       }
+       for (j = 1; j < lennew + 1; j++)
+               directions[0][j] = NEW;
+
+       for (i = 1, baseend = base; i < origbaselen + 1; i++) {
+               for (j = 1, newend = new; j < lennew + 1; j++) {
+                       if (match_string_spaces(baseend->line, baseend->len,
+                                               newend->line, newend->len, flags)) {
+                               lcs[i][j] = lcs[i - 1][j - 1] + 1;
+                               directions[i][j] = MATCH;
+                       } else if (lcs[i][j - 1] >= lcs[i - 1][j]) {
+                               lcs[i][j] = lcs[i][j - 1];
+                               directions[i][j] = NEW;
+                       } else {
+                               lcs[i][j] = lcs[i - 1][j];
+                               directions[i][j] = BASE;
+                       }
+                       if (newend->next)
+                               newend = newend->next;
+               }
+               if (baseend->next)
+                       baseend = baseend->next;
+       }
+
+       for (i = 0; i < origbaselen + 1; i++)
+               free(lcs[i]);
+       free(lcs);
+
+       /* At this point, baseend and newend point to the end of each lists */
+       i--;
+       j--;
+       while (i != 0 || j != 0) {
+               if (directions[i][j] == MATCH) {
+                       baseend->parent_map |= 1<<parent;
+                       baseend = baseend->prev;
+                       newend = newend->prev;
+                       i--;
+                       j--;
+               } else if (directions[i][j] == NEW) {
+                       struct lline *lline;
+
+                       lline = newend;
+                       /* Remove lline from new list and update newend */
+                       if (lline->prev)
+                               lline->prev->next = lline->next;
+                       else
+                               new = lline->next;
+                       if (lline->next)
+                               lline->next->prev = lline->prev;
+
+                       newend = lline->prev;
+                       j--;
+
+                       /* Add lline to base list */
+                       if (baseend) {
+                               lline->next = baseend->next;
+                               lline->prev = baseend;
+                               if (lline->prev)
+                                       lline->prev->next = lline;
+                       }
+                       else {
+                               lline->next = base;
+                               base = lline;
+                       }
+                       (*lenbase)++;
+
+                       if (lline->next)
+                               lline->next->prev = lline;
+
+               } else {
+                       baseend = baseend->prev;
+                       i--;
+               }
+       }
+
+       newend = new;
+       while (newend) {
+               struct lline *lline = newend;
+               newend = newend->next;
+               free(lline);
+       }
+
+       for (i = 0; i < origbaselen + 1; i++)
+               free(directions[i]);
+       free(directions);
+
+       return base;
+}
+
 static char *grab_blob(const unsigned char *sha1, unsigned int mode,
                       unsigned long *size, struct userdiff_driver *textconv,
                       const char *path)
@@ -129,29 +304,19 @@ static void append_lost(struct sline *sline, int n, const char *line, int len)
        if (line[len-1] == '\n')
                len--;
 
-       /* Check to see if we can squash things */
-       if (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;
-               }
-       }
-
        lline = xmalloc(sizeof(*lline) + len + 1);
        lline->len = len;
        lline->next = NULL;
+       lline->prev = sline->plost.lost_tail;
+       if (lline->prev)
+               lline->prev->next = lline;
+       else
+               sline->plost.lost_head = lline;
+       sline->plost.lost_tail = lline;
+       sline->plost.len++;
        lline->parent_map = this_mask;
        memcpy(lline->line, line, len);
        lline->line[len] = 0;
-       *sline->lost_tail = lline;
-       sline->lost_tail = &lline->next;
-       sline->next_lost = NULL;
 }
 
 struct combine_diff_state {
@@ -194,7 +359,6 @@ static void consume_line(void *state_, char *line, unsigned long len)
                                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)
@@ -215,7 +379,7 @@ static void combine_diff(const unsigned char *parent, unsigned int mode,
                         struct sline *sline, unsigned int cnt, int n,
                         int num_parent, int result_deleted,
                         struct userdiff_driver *textconv,
-                        const char *path)
+                        const char *path, long flags)
 {
        unsigned int p_lno, lno;
        unsigned long nmask = (1UL << n);
@@ -231,7 +395,7 @@ static void combine_diff(const unsigned char *parent, unsigned int mode,
        parent_file.ptr = grab_blob(parent, mode, &sz, textconv, path);
        parent_file.size = sz;
        memset(&xpp, 0, sizeof(xpp));
-       xpp.flags = 0;
+       xpp.flags = flags;
        memset(&xecfg, 0, sizeof(xecfg));
        memset(&state, 0, sizeof(state));
        state.nmask = nmask;
@@ -255,8 +419,18 @@ static void combine_diff(const unsigned char *parent, unsigned int mode,
                struct lline *ll;
                sline[lno].p_lno[n] = p_lno;
 
+               /* Coalesce new lines */
+               if (sline[lno].plost.lost_head) {
+                       struct sline *sl = &sline[lno];
+                       sl->lost = coalesce_lines(sl->lost, &sl->lenlost,
+                                                 sl->plost.lost_head,
+                                                 sl->plost.len, n, flags);
+                       sl->plost.lost_head = sl->plost.lost_tail = NULL;
+                       sl->plost.len = 0;
+               }
+
                /* How many lines would this sline advance the p_lno? */
-               ll = sline[lno].lost_head;
+               ll = sline[lno].lost;
                while (ll) {
                        if (ll->parent_map & nmask)
                                p_lno++; /* '-' means parent had it */
@@ -276,7 +450,7 @@ static int interesting(struct sline *sline, unsigned long all_mask)
        /* If some parents lost lines here, or if we have added to
         * some parent, it is interesting.
         */
-       return ((sline->flag & all_mask) || sline->lost_head);
+       return ((sline->flag & all_mask) || sline->lost);
 }
 
 static unsigned long adjust_hunk_tail(struct sline *sline,
@@ -344,8 +518,11 @@ static int give_context(struct sline *sline, unsigned long cnt, int num_parent)
                unsigned long k;
 
                /* Paint a few lines before the first interesting line. */
-               while (j < i)
-                       sline[j++].flag |= mark | no_pre_delete;
+               while (j < i) {
+                       if (!(sline[j].flag & mark))
+                               sline[j].flag |= no_pre_delete;
+                       sline[j++].flag |= mark;
+               }
 
        again:
                /* we know up to i is to be included.  where does the
@@ -459,7 +636,7 @@ static int make_hunks(struct sline *sline, unsigned long cnt,
                has_interesting = 0;
                for (j = i; j < hunk_end && !has_interesting; j++) {
                        unsigned long this_diff = sline[j].flag & all_mask;
-                       struct lline *ll = sline[j].lost_head;
+                       struct lline *ll = sline[j].lost;
                        if (this_diff) {
                                /* This has some changes.  Is it the
                                 * same as others?
@@ -526,7 +703,8 @@ static void show_line_to_eol(const char *line, int len, const char *reset)
               saw_cr_at_eol ? "\r" : "");
 }
 
-static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
+static void dump_sline(struct sline *sline, const char *line_prefix,
+                      unsigned long cnt, int num_parent,
                       int use_color, int result_deleted)
 {
        unsigned long mark = (1UL<<num_parent);
@@ -582,7 +760,7 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                        rlines -= null_context;
                }
 
-               fputs(c_frag, stdout);
+               printf("%s%s", line_prefix, c_frag);
                for (i = 0; i <= num_parent; i++) putchar(combine_marker);
                for (i = 0; i < num_parent; i++)
                        show_parent_lno(sline, lno, hunk_end, i, null_context);
@@ -612,9 +790,9 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                        int j;
                        unsigned long p_mask;
                        struct sline *sl = &sline[lno++];
-                       ll = (sl->flag & no_pre_delete) ? NULL : sl->lost_head;
+                       ll = (sl->flag & no_pre_delete) ? NULL : sl->lost;
                        while (ll) {
-                               fputs(c_old, stdout);
+                               printf("%s%s", line_prefix, c_old);
                                for (j = 0; j < num_parent; j++) {
                                        if (ll->parent_map & (1UL<<j))
                                                putchar('-');
@@ -627,6 +805,7 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                        if (cnt < lno)
                                break;
                        p_mask = 1;
+                       fputs(line_prefix, stdout);
                        if (!(sl->flag & (mark-1))) {
                                /*
                                 * This sline was here to hang the
@@ -662,7 +841,7 @@ static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
        jmask = (1UL<<j);
 
        for (lno = 0; lno <= cnt; lno++) {
-               struct lline *ll = sline->lost_head;
+               struct lline *ll = sline->lost;
                sline->p_lno[i] = sline->p_lno[j];
                while (ll) {
                        if (ll->parent_map & jmask)
@@ -680,11 +859,13 @@ static void reuse_combine_diff(struct sline *sline, unsigned long cnt,
 static void dump_quoted_path(const char *head,
                             const char *prefix,
                             const char *path,
+                            const char *line_prefix,
                             const char *c_meta, const char *c_reset)
 {
        static struct strbuf buf = STRBUF_INIT;
 
        strbuf_reset(&buf);
+       strbuf_addstr(&buf, line_prefix);
        strbuf_addstr(&buf, c_meta);
        strbuf_addstr(&buf, head);
        quote_two_c_style(&buf, prefix, path, 0);
@@ -696,6 +877,7 @@ static void show_combined_header(struct combine_diff_path *elem,
                                 int num_parent,
                                 int dense,
                                 struct rev_info *rev,
+                                const char *line_prefix,
                                 int mode_differs,
                                 int show_file_header)
 {
@@ -714,8 +896,8 @@ static void show_combined_header(struct combine_diff_path *elem,
                show_log(rev);
 
        dump_quoted_path(dense ? "diff --cc " : "diff --combined ",
-                        "", elem->path, c_meta, c_reset);
-       printf("%sindex ", c_meta);
+                        "", elem->path, line_prefix, c_meta, c_reset);
+       printf("%s%sindex ", line_prefix, c_meta);
        for (i = 0; i < num_parent; i++) {
                abb = find_unique_abbrev(elem->parent[i].sha1,
                                         abbrev);
@@ -734,11 +916,12 @@ static void show_combined_header(struct combine_diff_path *elem,
                            DIFF_STATUS_ADDED)
                                added = 0;
                if (added)
-                       printf("%snew file mode %06o",
-                              c_meta, elem->mode);
+                       printf("%s%snew file mode %06o",
+                              line_prefix, c_meta, elem->mode);
                else {
                        if (deleted)
-                               printf("%sdeleted file ", c_meta);
+                               printf("%s%sdeleted file ",
+                                      line_prefix, c_meta);
                        printf("mode ");
                        for (i = 0; i < num_parent; i++) {
                                printf("%s%06o", i ? "," : "",
@@ -755,16 +938,16 @@ static void show_combined_header(struct combine_diff_path *elem,
 
        if (added)
                dump_quoted_path("--- ", "", "/dev/null",
-                                c_meta, c_reset);
+                                line_prefix, c_meta, c_reset);
        else
                dump_quoted_path("--- ", a_prefix, elem->path,
-                                c_meta, c_reset);
+                                line_prefix, c_meta, c_reset);
        if (deleted)
                dump_quoted_path("+++ ", "", "/dev/null",
-                                c_meta, c_reset);
+                                line_prefix, c_meta, c_reset);
        else
                dump_quoted_path("+++ ", b_prefix, elem->path,
-                                c_meta, c_reset);
+                                line_prefix, c_meta, c_reset);
 }
 
 static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
@@ -782,6 +965,7 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
        struct userdiff_driver *userdiff;
        struct userdiff_driver *textconv = NULL;
        int is_binary;
+       const char *line_prefix = diff_line_prefix(opt);
 
        context = opt->context;
        userdiff = userdiff_find_by_path(elem->path);
@@ -901,7 +1085,7 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
        }
        if (is_binary) {
                show_combined_header(elem, num_parent, dense, rev,
-                                    mode_differs, 0);
+                                    line_prefix, mode_differs, 0);
                printf("Binary files differ\n");
                free(result);
                return;
@@ -916,10 +1100,6 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
 
        sline = xcalloc(cnt+2, sizeof(*sline));
        sline[0].bol = result;
-       for (lno = 0; lno <= cnt + 1; lno++) {
-               sline[lno].lost_tail = &sline[lno].lost_head;
-               sline[lno].flag = 0;
-       }
        for (lno = 0, cp = result; cp < result + result_size; cp++) {
                if (*cp == '\n') {
                        sline[lno].len = cp - sline[lno].bol;
@@ -955,22 +1135,22 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                                     elem->parent[i].mode,
                                     &result_file, sline,
                                     cnt, i, num_parent, result_deleted,
-                                    textconv, elem->path);
+                                    textconv, elem->path, opt->xdl_opts);
        }
 
        show_hunks = make_hunks(sline, cnt, num_parent, dense);
 
        if (show_hunks || mode_differs || working_tree_file) {
                show_combined_header(elem, num_parent, dense, rev,
-                                    mode_differs, 1);
-               dump_sline(sline, cnt, num_parent,
+                                    line_prefix, mode_differs, 1);
+               dump_sline(sline, line_prefix, cnt, num_parent,
                           opt->use_color, result_deleted);
        }
        free(result);
 
        for (lno = 0; lno < cnt; lno++) {
-               if (sline[lno].lost_head) {
-                       struct lline *ll = sline[lno].lost_head;
+               if (sline[lno].lost) {
+                       struct lline *ll = sline[lno].lost;
                        while (ll) {
                                struct lline *tmp = ll;
                                ll = ll->next;
@@ -986,6 +1166,7 @@ static void show_raw_diff(struct combine_diff_path *p, int num_parent, struct re
 {
        struct diff_options *opt = &rev->diffopt;
        int line_termination, inter_name_termination, i;
+       const char *line_prefix = diff_line_prefix(opt);
 
        line_termination = opt->line_termination;
        inter_name_termination = '\t';
@@ -995,7 +1176,10 @@ static void show_raw_diff(struct combine_diff_path *p, int num_parent, struct re
        if (rev->loginfo && !rev->no_commit_id)
                show_log(rev);
 
+
        if (opt->output_format & DIFF_FORMAT_RAW) {
+               printf("%s", line_prefix);
+
                /* As many colons as there are parents */
                for (i = 0; i < num_parent; i++)
                        putchar(':');
@@ -1033,6 +1217,7 @@ void show_combined_diff(struct combine_diff_path *p,
                       struct rev_info *rev)
 {
        struct diff_options *opt = &rev->diffopt;
+
        if (!p->len)
                return;
        if (opt->output_format & (DIFF_FORMAT_RAW |
@@ -1144,8 +1329,10 @@ void diff_tree_combined(const unsigned char *sha1,
 
                if (show_log_first && i == 0) {
                        show_log(rev);
+
                        if (rev->verbose_header && opt->output_format)
-                               putchar(opt->line_termination);
+                               printf("%s%c", diff_line_prefix(opt),
+                                      opt->line_termination);
                }
                diff_flush(&diffopts);
        }
@@ -1173,7 +1360,8 @@ void diff_tree_combined(const unsigned char *sha1,
 
                if (opt->output_format & DIFF_FORMAT_PATCH) {
                        if (needsep)
-                               putchar(opt->line_termination);
+                               printf("%s%c", diff_line_prefix(opt),
+                                      opt->line_termination);
                        for (p = paths; p; p = p->next) {
                                if (p->len)
                                        show_patch_diff(p, num_parent, dense,