fetch: Speed up fetch of large numbers of refs
[gitweb.git] / combine-diff.c
index 9f80a1c5e3a461afd11966625589684d61187911..5b63af1eeb71907f23117bc552fa7a4019f09722 100644 (file)
@@ -6,6 +6,7 @@
 #include "quote.h"
 #include "xdiff-interface.h"
 #include "log-tree.h"
+#include "refs.h"
 
 static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr, int n, int num_parent)
 {
@@ -23,7 +24,7 @@ static struct combine_diff_path *intersect_paths(struct combine_diff_path *curr,
                        path = q->queue[i]->two->path;
                        len = strlen(path);
                        p = xmalloc(combine_diff_path_size(num_parent, len));
-                       p->path = (char*) &(p->parent[num_parent]);
+                       p->path = (char *) &(p->parent[num_parent]);
                        memcpy(p->path, path, len);
                        p->path[len] = 0;
                        p->len = len;
@@ -79,6 +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.
@@ -90,18 +92,24 @@ struct sline {
        unsigned long *p_lno;
 };
 
-static char *grab_blob(const unsigned char *sha1, unsigned long *size)
+static char *grab_blob(const unsigned char *sha1, unsigned int mode, unsigned long *size)
 {
        char *blob;
        enum object_type type;
-       if (is_null_sha1(sha1)) {
+
+       if (S_ISGITLINK(mode)) {
+               blob = xmalloc(100);
+               *size = snprintf(blob, 100,
+                                "Subproject commit %s\n", sha1_to_hex(sha1));
+       } else if (is_null_sha1(sha1)) {
                /* deleted blob */
                *size = 0;
                return xcalloc(1, 1);
+       } else {
+               blob = read_sha1_file(sha1, &type, size);
+               if (type != OBJ_BLOB)
+                       die("object '%s' is not a blob!", sha1_to_hex(sha1));
        }
-       blob = read_sha1_file(sha1, &type, size);
-       if (type != OBJ_BLOB)
-               die("object '%s' is not a blob!", sha1_to_hex(sha1));
        return blob;
 }
 
@@ -114,18 +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;
@@ -140,11 +142,10 @@ 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 {
-       struct xdiff_emit_state xm;
-
        unsigned int lno;
        int ob, on, nb, nn;
        unsigned long nmask;
@@ -163,25 +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)
@@ -197,7 +201,8 @@ static void consume_line(void *state_, char *line, unsigned long len)
        }
 }
 
-static void combine_diff(const unsigned char *parent, mmfile_t *result_file,
+static void combine_diff(const unsigned char *parent, unsigned int mode,
+                        mmfile_t *result_file,
                         struct sline *sline, unsigned int cnt, int n,
                         int num_parent)
 {
@@ -213,21 +218,20 @@ static void combine_diff(const unsigned char *parent, mmfile_t *result_file,
        if (!cnt)
                return; /* result deleted */
 
-       parent_file.ptr = grab_blob(parent, &sz);
+       parent_file.ptr = grab_blob(parent, mode, &sz);
        parent_file.size = sz;
+       memset(&xpp, 0, sizeof(xpp));
        xpp.flags = XDF_NEED_MINIMAL;
        memset(&xecfg, 0, sizeof(xecfg));
-       ecb.outf = xdiff_outf;
-       ecb.priv = &state;
        memset(&state, 0, sizeof(state));
-       state.xm.consume = consume_line;
        state.nmask = nmask;
        state.sline = sline;
        state.lno = 1;
        state.num_parent = num_parent;
        state.n = n;
 
-       xdi_diff(&parent_file, result_file, &xpp, &xecfg, &ecb);
+       xdi_diff_outf(&parent_file, result_file, consume_line, &state,
+                     &xpp, &xecfg, &ecb);
        free(parent_file.ptr);
 
        /* Assign line numbers for this parent.
@@ -500,6 +504,18 @@ static int hunk_comment_line(const char *bol)
        return (isalpha(ch) || ch == '_' || ch == '$');
 }
 
+static void show_line_to_eol(const char *line, int len, const char *reset)
+{
+       int saw_cr_at_eol = 0;
+       if (len < 0)
+               len = strlen(line);
+       saw_cr_at_eol = (len && line[len-1] == '\r');
+
+       printf("%.*s%s%s\n", len - saw_cr_at_eol, line,
+              reset,
+              saw_cr_at_eol ? "\r" : "");
+}
+
 static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                       int use_color)
 {
@@ -517,7 +533,6 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                return; /* result deleted */
 
        while (1) {
-               struct sline *sl = &sline[lno];
                unsigned long hunk_end;
                unsigned long rlines;
                const char *hunk_comment = NULL;
@@ -583,7 +598,7 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                        struct lline *ll;
                        int j;
                        unsigned long p_mask;
-                       sl = &sline[lno++];
+                       struct sline *sl = &sline[lno++];
                        ll = (sl->flag & no_pre_delete) ? NULL : sl->lost_head;
                        while (ll) {
                                fputs(c_old, stdout);
@@ -593,7 +608,7 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                                        else
                                                putchar(' ');
                                }
-                               printf("%s%s\n", ll->line, c_reset);
+                               show_line_to_eol(ll->line, -1, c_reset);
                                ll = ll->next;
                        }
                        if (cnt < lno)
@@ -617,7 +632,7 @@ static void dump_sline(struct sline *sline, unsigned long cnt, int num_parent,
                                        putchar(' ');
                                p_mask <<= 1;
                        }
-                       printf("%.*s%s\n", sl->len, sl->bol, c_reset);
+                       show_line_to_eol(sl->bol, sl->len, c_reset);
                }
        }
 }
@@ -675,12 +690,16 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
        int i, show_hunks;
        int working_tree_file = is_null_sha1(elem->sha1);
        int abbrev = DIFF_OPT_TST(opt, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
+       const char *a_prefix, *b_prefix;
        mmfile_t result_file;
 
        context = opt->context;
+       a_prefix = opt->a_prefix ? opt->a_prefix : "a/";
+       b_prefix = opt->b_prefix ? opt->b_prefix : "b/";
+
        /* Read the result of merge first */
        if (!working_tree_file)
-               result = grab_blob(elem->sha1, &result_size);
+               result = grab_blob(elem->sha1, elem->mode, &result_size);
        else {
                /* Used by diff-tree to read from the working tree */
                struct stat st;
@@ -690,19 +709,23 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                        goto deleted_file;
 
                if (S_ISLNK(st.st_mode)) {
-                       size_t len = xsize_t(st.st_size);
-                       result_size = len;
-                       result = xmalloc(len + 1);
-                       if (result_size != readlink(elem->path, result, len)) {
+                       struct strbuf buf = STRBUF_INIT;
+
+                       if (strbuf_readlink(&buf, elem->path, st.st_size) < 0) {
                                error("readlink(%s): %s", elem->path,
                                      strerror(errno));
                                return;
                        }
-                       result[len] = 0;
+                       result_size = buf.len;
+                       result = strbuf_detach(&buf, NULL);
                        elem->mode = canon_mode(st.st_mode);
-               }
-               else if (0 <= (fd = open(elem->path, O_RDONLY)) &&
-                        !fstat(fd, &st)) {
+               } else if (S_ISDIR(st.st_mode)) {
+                       unsigned char sha1[20];
+                       if (resolve_gitlink_ref(elem->path, "HEAD", sha1) < 0)
+                               result = grab_blob(elem->sha1, elem->mode, &result_size);
+                       else
+                               result = grab_blob(sha1, elem->mode, &result_size);
+               } else if (0 <= (fd = open(elem->path, O_RDONLY))) {
                        size_t len = xsize_t(st.st_size);
                        ssize_t done;
                        int is_file, i;
@@ -722,11 +745,22 @@ 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);
 
                        result[len] = 0;
+
+                       /* If not a fake symlink, apply filters, e.g. autocrlf */
+                       if (is_file) {
+                               struct strbuf buf = STRBUF_INIT;
+
+                               if (convert_to_git(elem->path, result, len, &buf, safe_crlf)) {
+                                       free(result);
+                                       result = strbuf_detach(&buf, &len);
+                                       result_size = len;
+                               }
+                       }
                }
                else {
                deleted_file:
@@ -783,7 +817,9 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                        }
                }
                if (i <= j)
-                       combine_diff(elem->parent[i].sha1, &result_file, sline,
+                       combine_diff(elem->parent[i].sha1,
+                                    elem->parent[i].mode,
+                                    &result_file, sline,
                                     cnt, i, num_parent);
                if (elem->parent[i].mode != elem->mode)
                        mode_differs = 1;
@@ -841,13 +877,13 @@ static void show_patch_diff(struct combine_diff_path *elem, int num_parent,
                        dump_quoted_path("--- ", "", "/dev/null",
                                         c_meta, c_reset);
                else
-                       dump_quoted_path("--- ", opt->a_prefix, elem->path,
+                       dump_quoted_path("--- ", a_prefix, elem->path,
                                         c_meta, c_reset);
                if (deleted)
                        dump_quoted_path("+++ ", "", "/dev/null",
                                         c_meta, c_reset);
                else
-                       dump_quoted_path("+++ ", opt->b_prefix, elem->path,
+                       dump_quoted_path("+++ ", b_prefix, elem->path,
                                         c_meta, c_reset);
                dump_sline(sline, cnt, num_parent,
                           DIFF_OPT_TST(opt, COLOR_DIFF));
@@ -1026,7 +1062,7 @@ void diff_tree_combined_merge(const unsigned char *sha1,
        for (parents = commit->parents, num_parent = 0;
             parents;
             parents = parents->next, num_parent++)
-               hashcpy((unsigned char*)(parent + num_parent),
+               hashcpy((unsigned char *)(parent + num_parent),
                        parents->item->object.sha1);
        diff_tree_combined(sha1, parent, num_parent, dense, rev);
 }