do not write null sha1s to on-disk index
[gitweb.git] / diffcore-rename.c
index d6fd3cacd6de4757994c61903dd07e0c4d74a9e9..e6f9be64cfed2984f1ebd0364ae1e9bfabc35de7 100644 (file)
@@ -5,6 +5,7 @@
 #include "diff.h"
 #include "diffcore.h"
 #include "hash.h"
+#include "progress.h"
 
 /* Table of rename/copy destinations */
 
@@ -47,29 +48,30 @@ static struct diff_rename_dst *locate_rename_dst(struct diff_filespec *two,
                memmove(rename_dst + first + 1, rename_dst + first,
                        (rename_dst_nr - first - 1) * sizeof(*rename_dst));
        rename_dst[first].two = alloc_filespec(two->path);
-       fill_filespec(rename_dst[first].two, two->sha1, two->mode);
+       fill_filespec(rename_dst[first].two, two->sha1, two->sha1_valid, two->mode);
        rename_dst[first].pair = NULL;
        return &(rename_dst[first]);
 }
 
 /* Table of rename/copy src files */
 static struct diff_rename_src {
-       struct diff_filespec *one;
+       struct diff_filepair *p;
        unsigned short score; /* to remember the break score */
 } *rename_src;
 static int rename_src_nr, rename_src_alloc;
 
-static struct diff_rename_src *register_rename_src(struct diff_filespec *one,
-                                                  unsigned short score)
+static struct diff_rename_src *register_rename_src(struct diff_filepair *p)
 {
        int first, last;
+       struct diff_filespec *one = p->one;
+       unsigned short score = p->score;
 
        first = 0;
        last = rename_src_nr;
        while (last > first) {
                int next = (last + first) >> 1;
                struct diff_rename_src *src = &(rename_src[next]);
-               int cmp = strcmp(one->path, src->one->path);
+               int cmp = strcmp(one->path, src->p->one->path);
                if (!cmp)
                        return src;
                if (cmp < 0) {
@@ -89,7 +91,7 @@ static struct diff_rename_src *register_rename_src(struct diff_filespec *one,
        if (first < rename_src_nr)
                memmove(rename_src + first + 1, rename_src + first,
                        (rename_src_nr - first - 1) * sizeof(*rename_src));
-       rename_src[first].one = one;
+       rename_src[first].p = p;
        rename_src[first].score = score;
        return &(rename_src[first]);
 }
@@ -170,7 +172,7 @@ static int estimate_similarity(struct diff_filespec *src,
         * and the final score computation below would not have a
         * divide-by-zero issue.
         */
-       if (base_size * (MAX_SCORE-minimum_score) < delta_size * MAX_SCORE)
+       if (max_size * (MAX_SCORE-minimum_score) < delta_size * MAX_SCORE)
                return 0;
 
        if (!src->cnt_data && diff_populate_filespec(src, 0))
@@ -204,7 +206,7 @@ static void record_rename_pair(int dst_index, int src_index, int score)
        if (rename_dst[dst_index].pair)
                die("internal error: dst already matched.");
 
-       src = rename_src[src_index].one;
+       src = rename_src[src_index].p->one;
        src->rename_used++;
        src->count++;
 
@@ -247,7 +249,8 @@ struct file_similarity {
 };
 
 static int find_identical_files(struct file_similarity *src,
-                               struct file_similarity *dst)
+                               struct file_similarity *dst,
+                               struct diff_options *options)
 {
        int renames = 0;
 
@@ -277,6 +280,8 @@ static int find_identical_files(struct file_similarity *src,
                        }
                        /* Give higher scores to sources that haven't been used already */
                        score = !source->rename_used;
+                       if (source->rename_used && options->detect_rename != DIFF_DETECT_COPY)
+                               continue;
                        score += basename_same(source, target);
                        if (score > best_score) {
                                best = p;
@@ -306,11 +311,12 @@ static void free_similarity_list(struct file_similarity *p)
        }
 }
 
-static int find_same_files(void *ptr)
+static int find_same_files(void *ptr, void *data)
 {
        int ret;
        struct file_similarity *p = ptr;
        struct file_similarity *src = NULL, *dst = NULL;
+       struct diff_options *options = data;
 
        /* Split the hash list up into sources and destinations */
        do {
@@ -329,7 +335,7 @@ static int find_same_files(void *ptr)
         * If we have both sources *and* destinations, see if
         * we can match them up
         */
-       ret = (src && dst) ? find_identical_files(src, dst) : 0;
+       ret = (src && dst) ? find_identical_files(src, dst, options) : 0;
 
        /* Free the hashes and return the number of renames found */
        free_similarity_list(src);
@@ -377,20 +383,20 @@ static void insert_file_table(struct hash_table *table, int src_dst, int index,
  * and then during the second round we try to match
  * cache-dirty entries as well.
  */
-static int find_exact_renames(void)
+static int find_exact_renames(struct diff_options *options)
 {
        int i;
        struct hash_table file_table;
 
        init_hash(&file_table);
        for (i = 0; i < rename_src_nr; i++)
-               insert_file_table(&file_table, -1, i, rename_src[i].one);
+               insert_file_table(&file_table, -1, i, rename_src[i].p->one);
 
        for (i = 0; i < rename_dst_nr; i++)
                insert_file_table(&file_table, 1, i, rename_dst[i].two);
 
        /* Find the renames */
-       i = for_each_hash(&file_table, find_same_files);
+       i = for_each_hash(&file_table, find_same_files, options);
 
        /* .. and free the hash data structure */
        free_hash(&file_table);
@@ -414,16 +420,86 @@ static void record_if_better(struct diff_score m[], struct diff_score *o)
                m[worst] = *o;
 }
 
+/*
+ * Returns:
+ * 0 if we are under the limit;
+ * 1 if we need to disable inexact rename detection;
+ * 2 if we would be under the limit if we were given -C instead of -C -C.
+ */
+static int too_many_rename_candidates(int num_create,
+                                     struct diff_options *options)
+{
+       int rename_limit = options->rename_limit;
+       int num_src = rename_src_nr;
+       int i;
+
+       options->needed_rename_limit = 0;
+
+       /*
+        * This basically does a test for the rename matrix not
+        * growing larger than a "rename_limit" square matrix, ie:
+        *
+        *    num_create * num_src > rename_limit * rename_limit
+        *
+        * but handles the potential overflow case specially (and we
+        * assume at least 32-bit integers)
+        */
+       if (rename_limit <= 0 || rename_limit > 32767)
+               rename_limit = 32767;
+       if ((num_create <= rename_limit || num_src <= rename_limit) &&
+           (num_create * num_src <= rename_limit * rename_limit))
+               return 0;
+
+       options->needed_rename_limit =
+               num_src > num_create ? num_src : num_create;
+
+       /* Are we running under -C -C? */
+       if (!DIFF_OPT_TST(options, FIND_COPIES_HARDER))
+               return 1;
+
+       /* Would we bust the limit if we were running under -C? */
+       for (num_src = i = 0; i < rename_src_nr; i++) {
+               if (diff_unmodified_pair(rename_src[i].p))
+                       continue;
+               num_src++;
+       }
+       if ((num_create <= rename_limit || num_src <= rename_limit) &&
+           (num_create * num_src <= rename_limit * rename_limit))
+               return 2;
+       return 1;
+}
+
+static int find_renames(struct diff_score *mx, int dst_cnt, int minimum_score, int copies)
+{
+       int count = 0, i;
+
+       for (i = 0; i < dst_cnt * NUM_CANDIDATE_PER_DST; i++) {
+               struct diff_rename_dst *dst;
+
+               if ((mx[i].dst < 0) ||
+                   (mx[i].score < minimum_score))
+                       break; /* there is no more usable pair. */
+               dst = &rename_dst[mx[i].dst];
+               if (dst->pair)
+                       continue; /* already done, either exact or fuzzy. */
+               if (!copies && rename_src[mx[i].src].p->one->rename_used)
+                       continue;
+               record_rename_pair(mx[i].dst, mx[i].src, mx[i].score);
+               count++;
+       }
+       return count;
+}
+
 void diffcore_rename(struct diff_options *options)
 {
        int detect_rename = options->detect_rename;
        int minimum_score = options->rename_score;
-       int rename_limit = options->rename_limit;
        struct diff_queue_struct *q = &diff_queued_diff;
        struct diff_queue_struct outq;
        struct diff_score *mx;
-       int i, j, rename_count;
-       int num_create, num_src, dst_cnt;
+       int i, j, rename_count, skip_unmodified = 0;
+       int num_create, dst_cnt;
+       struct progress *progress = NULL;
 
        if (!minimum_score)
                minimum_score = DEFAULT_RENAME_SCORE;
@@ -439,7 +515,7 @@ void diffcore_rename(struct diff_options *options)
                        else
                                locate_rename_dst(p->two, 1);
                }
-               else if (!DIFF_FILE_VALID(p->two)) {
+               else if (!DIFF_PAIR_UNMERGED(p) && !DIFF_FILE_VALID(p->two)) {
                        /*
                         * If the source is a broken "delete", and
                         * they did not really want to get broken,
@@ -449,7 +525,7 @@ void diffcore_rename(struct diff_options *options)
                         */
                        if (p->broken_pair && !p->score)
                                p->one->rename_used++;
-                       register_rename_src(p->one, p->score);
+                       register_rename_src(p);
                }
                else if (detect_rename == DIFF_DETECT_COPY) {
                        /*
@@ -457,7 +533,7 @@ void diffcore_rename(struct diff_options *options)
                         * one, to indicate ourselves as a user.
                         */
                        p->one->rename_used++;
-                       register_rename_src(p->one, p->score);
+                       register_rename_src(p);
                }
        }
        if (rename_dst_nr == 0 || rename_src_nr == 0)
@@ -467,7 +543,7 @@ void diffcore_rename(struct diff_options *options)
         * We really want to cull the candidates list early
         * with cheap tests in order to avoid doing deltas.
         */
-       rename_count = find_exact_renames();
+       rename_count = find_exact_renames(options);
 
        /* Did we only want exact renames? */
        if (minimum_score == MAX_SCORE)
@@ -478,28 +554,26 @@ void diffcore_rename(struct diff_options *options)
         * files still remain as options for rename/copies!)
         */
        num_create = (rename_dst_nr - rename_count);
-       num_src = rename_src_nr;
 
        /* All done? */
        if (!num_create)
                goto cleanup;
 
-       /*
-        * This basically does a test for the rename matrix not
-        * growing larger than a "rename_limit" square matrix, ie:
-        *
-        *    num_create * num_src > rename_limit * rename_limit
-        *
-        * but handles the potential overflow case specially (and we
-        * assume at least 32-bit integers)
-        */
-       if (rename_limit <= 0 || rename_limit > 32767)
-               rename_limit = 32767;
-       if ((num_create > rename_limit && num_src > rename_limit) ||
-           (num_create * num_src > rename_limit * rename_limit)) {
-               if (options->warn_on_too_large_rename)
-                       warning("too many files (created: %d deleted: %d), skipping inexact rename detection", num_create, num_src);
+       switch (too_many_rename_candidates(num_create, options)) {
+       case 1:
                goto cleanup;
+       case 2:
+               options->degraded_cc_to_c = 1;
+               skip_unmodified = 1;
+               break;
+       default:
+               break;
+       }
+
+       if (options->show_rename_progress) {
+               progress = start_progress_delay(
+                               "Performing inexact rename detection",
+                               rename_dst_nr * rename_src_nr, 50, 1);
        }
 
        mx = xcalloc(num_create * NUM_CANDIDATE_PER_DST, sizeof(*mx));
@@ -515,8 +589,13 @@ void diffcore_rename(struct diff_options *options)
                        m[j].dst = -1;
 
                for (j = 0; j < rename_src_nr; j++) {
-                       struct diff_filespec *one = rename_src[j].one;
+                       struct diff_filespec *one = rename_src[j].p->one;
                        struct diff_score this_src;
+
+                       if (skip_unmodified &&
+                           diff_unmodified_pair(rename_src[j].p))
+                               continue;
+
                        this_src.score = estimate_similarity(one, two,
                                                             minimum_score);
                        this_src.name_score = basename_same(one, two);
@@ -531,51 +610,31 @@ void diffcore_rename(struct diff_options *options)
                        diff_free_filespec_blob(two);
                }
                dst_cnt++;
+               display_progress(progress, (i+1)*rename_src_nr);
        }
+       stop_progress(&progress);
 
        /* cost matrix sorted by most to least similar pair */
        qsort(mx, dst_cnt * NUM_CANDIDATE_PER_DST, sizeof(*mx), score_compare);
 
-       for (i = 0; i < dst_cnt * NUM_CANDIDATE_PER_DST; i++) {
-               struct diff_rename_dst *dst;
-
-               if ((mx[i].dst < 0) ||
-                   (mx[i].score < minimum_score))
-                       break; /* there is no more usable pair. */
-               dst = &rename_dst[mx[i].dst];
-               if (dst->pair)
-                       continue; /* already done, either exact or fuzzy. */
-               if (rename_src[mx[i].src].one->rename_used)
-                       continue;
-               record_rename_pair(mx[i].dst, mx[i].src, mx[i].score);
-               rename_count++;
-       }
-
-       for (i = 0; i < dst_cnt * NUM_CANDIDATE_PER_DST; i++) {
-               struct diff_rename_dst *dst;
-
-               if ((mx[i].dst < 0) ||
-                   (mx[i].score < minimum_score))
-                       break; /* there is no more usable pair. */
-               dst = &rename_dst[mx[i].dst];
-               if (dst->pair)
-                       continue; /* already done, either exact or fuzzy. */
-               record_rename_pair(mx[i].dst, mx[i].src, mx[i].score);
-               rename_count++;
-       }
+       rename_count += find_renames(mx, dst_cnt, minimum_score, 0);
+       if (detect_rename == DIFF_DETECT_COPY)
+               rename_count += find_renames(mx, dst_cnt, minimum_score, 1);
        free(mx);
 
  cleanup:
        /* At this point, we have found some renames and copies and they
         * are recorded in rename_dst.  The original list is still in *q.
         */
-       outq.queue = NULL;
-       outq.nr = outq.alloc = 0;
+       DIFF_QUEUE_CLEAR(&outq);
        for (i = 0; i < q->nr; i++) {
                struct diff_filepair *p = q->queue[i];
                struct diff_filepair *pair_to_free = NULL;
 
-               if (!DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
+               if (DIFF_PAIR_UNMERGED(p)) {
+                       diff_q(&outq, p);
+               }
+               else if (!DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
                        /*
                         * Creation
                         *