Merge branch 'lt/rev-list' into next
authorJunio C Hamano <junkio@cox.net>
Sun, 26 Feb 2006 23:33:49 +0000 (15:33 -0800)
committerJunio C Hamano <junkio@cox.net>
Sun, 26 Feb 2006 23:33:49 +0000 (15:33 -0800)
* lt/rev-list:
  First cut at libifying revlist generation
  Merge branch 'maint'
  sample hooks template.
  Teach the "git" command to handle some commands internally
  Use setenv(), fix warnings
  contrib/git-svn: version 0.10.0
  contrib/git-svn: optimize sequential commits to svn
  contrib/git-svn: add show-ignore command
  annotate: Use qx{} for pipes on activestate.
  annotate: Convert all -| calls to use a helper open_pipe().
  annotate: Handle dirty state and arbitrary revisions.
  git-fetch: print the new and old ref when fast-forwarding

Makefile
blame.c [new file with mode: 0644]
count-delta.c
diff-delta.c
diffcore.h

index 3575489..5e93f27 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -165,7 +165,7 @@ PROGRAMS = \
        git-upload-pack$X git-verify-pack$X git-write-tree$X \
        git-update-ref$X git-symbolic-ref$X git-check-ref-format$X \
        git-name-rev$X git-pack-redundant$X git-repo-config$X git-var$X \
-       git-describe$X git-merge-tree$X
+       git-describe$X git-merge-tree$X git-blame$X
 
 # what 'all' will build and 'install' will install, in gitexecdir
 ALL_PROGRAMS = $(PROGRAMS) $(SIMPLE_PROGRAMS) $(SCRIPTS)
diff --git a/blame.c b/blame.c
new file mode 100644 (file)
index 0000000..1e65546
--- /dev/null
+++ b/blame.c
@@ -0,0 +1,443 @@
+#include <assert.h>
+
+#include "cache.h"
+#include "refs.h"
+#include "tag.h"
+#include "commit.h"
+#include "tree.h"
+#include "blob.h"
+#include "epoch.h"
+#include "diff.h"
+
+#define DEBUG 0
+
+struct commit** blame_lines;
+int num_blame_lines;
+
+struct util_info
+{
+    int* line_map;
+    int num_lines;
+    unsigned char sha1[20]; /* blob sha, not commit! */
+    char* buf;
+    unsigned long size;
+//    const char* path;
+};
+
+struct chunk
+{
+    int off1, len1; // ---
+    int off2, len2; // +++
+};
+
+struct patch
+{
+    struct chunk* chunks;
+    int num;
+};
+
+static void get_blob(struct commit* commit);
+
+int num_get_patch = 0;
+int num_commits = 0;
+
+struct patch* get_patch(struct commit* commit, struct commit* other)
+{
+    struct patch* ret = xmalloc(sizeof(struct patch));
+    ret->chunks = NULL;
+    ret->num = 0;
+
+    struct util_info* info_c = (struct util_info*) commit->object.util;
+    struct util_info* info_o = (struct util_info*) other->object.util;
+
+    if(!memcmp(info_c->sha1, info_o->sha1, 20))
+        return ret;
+
+    get_blob(commit);
+    get_blob(other);
+
+    FILE* fout = fopen("/tmp/git-blame-tmp1", "w");
+    if(!fout)
+        die("fopen tmp1 failed: %s", strerror(errno));
+
+    if(fwrite(info_c->buf, info_c->size, 1, fout) != 1)
+        die("fwrite 1 failed: %s", strerror(errno));
+    fclose(fout);
+
+    fout = fopen("/tmp/git-blame-tmp2", "w");
+    if(!fout)
+        die("fopen tmp2 failed: %s", strerror(errno));
+
+    if(fwrite(info_o->buf, info_o->size, 1, fout) != 1)
+        die("fwrite 2 failed: %s", strerror(errno));
+    fclose(fout);
+
+    FILE* fin = popen("diff -u0 /tmp/git-blame-tmp1 /tmp/git-blame-tmp2", "r");
+    if(!fin)
+        die("popen failed: %s", strerror(errno));
+
+    char buf[1024];
+    while(fgets(buf, sizeof(buf), fin)) {
+        if(buf[0] != '@' || buf[1] != '@')
+            continue;
+
+        if(DEBUG)
+            printf("chunk line: %s", buf);
+        ret->num++;
+        ret->chunks = xrealloc(ret->chunks, sizeof(struct chunk)*ret->num);
+        struct chunk* chunk = &ret->chunks[ret->num-1];
+
+        assert(!strncmp(buf, "@@ -", 4));
+
+        char* start = buf+4;
+        char* sp = index(start, ' ');
+        *sp = '\0';
+        if(index(start, ',')) {
+            int ret = sscanf(start, "%d,%d", &chunk->off1, &chunk->len1);
+            assert(ret == 2);
+        } else {
+            int ret = sscanf(start, "%d", &chunk->off1);
+            assert(ret == 1);
+            chunk->len1 = 1;
+        }
+        *sp = ' ';
+
+        start = sp+1;
+        sp = index(start, ' ');
+        *sp = '\0';
+        if(index(start, ',')) {
+            int ret = sscanf(start, "%d,%d", &chunk->off2, &chunk->len2);
+            assert(ret == 2);
+        } else {
+            int ret = sscanf(start, "%d", &chunk->off2);
+            assert(ret == 1);
+            chunk->len2 = 1;
+        }
+        *sp = ' ';
+
+        if(chunk->off1 > 0)
+            chunk->off1 -= 1;
+        if(chunk->off2 > 0)
+            chunk->off2 -= 1;
+
+        assert(chunk->off1 >= 0);
+        assert(chunk->off2 >= 0);
+    }
+    fclose(fin);
+
+    num_get_patch++;
+    return ret;
+}
+
+void free_patch(struct patch* p)
+{
+    free(p->chunks);
+    free(p);
+}
+
+static int get_blob_sha1_internal(unsigned char *sha1, const char *base, int baselen,
+                                  const char *pathname, unsigned mode, int stage);
+
+
+static unsigned char blob_sha1[20];
+static int get_blob_sha1(struct tree* t, const char* pathname, unsigned char* sha1)
+{
+    const char *pathspec[2];
+    pathspec[0] = pathname;
+    pathspec[1] = NULL;
+    memset(blob_sha1, 0, sizeof(blob_sha1));
+    read_tree_recursive(t, "", 0, 0, pathspec, get_blob_sha1_internal);
+
+    int i;
+    for(i = 0; i < 20; i++) {
+        if(blob_sha1[i] != 0)
+            break;
+    }
+
+    if(i == 20)
+        return -1;
+
+    memcpy(sha1, blob_sha1, 20);
+    return 0;
+}
+
+static int get_blob_sha1_internal(unsigned char *sha1, const char *base, int baselen,
+                                  const char *pathname, unsigned mode, int stage)
+{
+//    printf("Got blob: %s base: '%s' baselen: %d pathname: '%s' mode: %o stage: %d\n",
+//           sha1_to_hex(sha1), base, baselen, pathname, mode, stage);
+
+    if(S_ISDIR(mode))
+        return READ_TREE_RECURSIVE;
+
+    memcpy(blob_sha1, sha1, 20);
+    return -1;
+}
+
+static void get_blob(struct commit* commit)
+{
+    struct util_info* info = commit->object.util;
+    char type[20];
+
+    if(info->buf)
+        return;
+
+    info->buf = read_sha1_file(info->sha1, type, &info->size);
+    assert(!strcmp(type, "blob"));
+}
+
+void print_patch(struct patch* p)
+{
+    printf("Num chunks: %d\n", p->num);
+    int i;
+    for(i = 0; i < p->num; i++) {
+        printf("%d,%d %d,%d\n", p->chunks[i].off1, p->chunks[i].len1, p->chunks[i].off2, p->chunks[i].len2);
+    }
+}
+
+
+// p is a patch from commit to other.
+void fill_line_map(struct commit* commit, struct commit* other, struct patch* p)
+{
+    int num_lines = ((struct util_info*) commit->object.util)->num_lines;
+    int* line_map = ((struct util_info*) commit->object.util)->line_map;
+    int num_lines2 = ((struct util_info*) other->object.util)->num_lines;
+    int* line_map2 = ((struct util_info*) other->object.util)->line_map;
+    int cur_chunk = 0;
+    int i1, i2;
+
+    if(p->num && DEBUG)
+        print_patch(p);
+
+    for(i1 = 0; i1 < num_lines; i1++)
+        line_map[i1] = -1;
+
+    if(DEBUG)
+        printf("num lines 1: %d num lines 2: %d\n", num_lines, num_lines2);
+
+    for(i1 = 0, i2 = 0; i1 < num_lines; i1++, i2++) {
+        if(DEBUG > 1)
+            printf("%d %d\n", i1, i2);
+
+        if(i2 >= num_lines2)
+            break;
+
+        line_map[i1] = line_map2[i2];
+
+        struct chunk* chunk = NULL;
+        if(cur_chunk < p->num)
+            chunk = &p->chunks[cur_chunk];
+
+        if(chunk && chunk->off1 == i1) {
+            i2 = chunk->off2;
+
+            if(chunk->len1 > 0)
+                i1 += chunk->len1-1;
+            if(chunk->len2 > 0)
+                i2 += chunk->len2-1;
+            cur_chunk++;
+        }
+    }
+}
+
+int map_line(struct commit* commit, int line)
+{
+    struct util_info* info = commit->object.util;
+    assert(line >= 0 && line < info->num_lines);
+    return info->line_map[line];
+}
+
+int fill_util_info(struct commit* commit, const char* path)
+{
+    if(commit->object.util)
+        return 0;
+
+    struct util_info* util = xmalloc(sizeof(struct util_info));
+    util->buf = NULL;
+    util->size = 0;
+    util->num_lines = -1;
+    util->line_map = NULL;
+
+    commit->object.util = util;
+
+    if(get_blob_sha1(commit->tree, path, util->sha1))
+        return -1;
+
+    return 0;
+}
+
+void alloc_line_map(struct commit* commit)
+{
+    struct util_info* util = commit->object.util;
+
+    if(util->line_map)
+        return;
+
+    get_blob(commit);
+
+    int i;
+    util->num_lines = 0;
+    for(i = 0; i < util->size; i++) {
+        if(util->buf[i] == '\n')
+            util->num_lines++;
+    }
+    util->line_map = xmalloc(sizeof(int)*util->num_lines);
+}
+
+void copy_line_map(struct commit* dst, struct commit* src)
+{
+    struct util_info* u_dst = dst->object.util;
+    struct util_info* u_src = src->object.util;
+
+    u_dst->line_map = u_src->line_map;
+    u_dst->num_lines = u_src->num_lines;
+    u_dst->buf = u_src->buf;
+    u_dst->size = u_src->size;
+}
+
+void process_commits(struct commit_list* list, const char* path)
+{
+    int i;
+
+    while(list) {
+        struct commit* commit = pop_commit(&list);
+        struct commit_list* parents;
+        struct util_info* info;
+
+        info = commit->object.util;
+        num_commits++;
+        if(DEBUG)
+            printf("\nProcessing commit: %d %s\n", num_commits, sha1_to_hex(commit->object.sha1));
+        for(parents = commit->parents;
+            parents != NULL; parents = parents->next) {
+            struct commit* parent = parents->item;
+
+            if(parse_commit(parent) < 0)
+                die("parse_commit error");
+
+            if(DEBUG)
+                printf("parent: %s\n", sha1_to_hex(parent->object.sha1));
+
+            if(fill_util_info(parent, path))
+                continue;
+
+            // Temporarily assign everything to the parent.
+            int num_blame = 0;
+            for(i = 0; i < num_blame_lines; i++) {
+                if(blame_lines[i] == commit) {
+                    num_blame++;
+                    blame_lines[i] = parent;
+                }
+            }
+
+            if(num_blame == 0)
+                continue;
+
+            struct patch* patch = get_patch(parent, commit);
+            if(patch->num == 0) {
+                copy_line_map(parent, commit);
+            } else {
+                alloc_line_map(parent);
+                fill_line_map(parent, commit, patch);
+            }
+
+            for(i = 0; i < patch->num; i++) {
+                int l;
+                for(l = 0; l < patch->chunks[i].len2; l++) {
+                    int mapped_line = map_line(commit, patch->chunks[i].off2 + l);
+                    if(mapped_line != -1 && blame_lines[mapped_line] == parent)
+                        blame_lines[mapped_line] = commit;
+                }
+            }
+            free_patch(patch);
+        }
+    }
+}
+
+#define SEEN 1
+struct commit_list* get_commit_list(struct commit* commit, const char* pathname)
+{
+    struct commit_list* ret = NULL;
+    struct commit_list* process = NULL;
+    unsigned char sha1[20];
+
+    commit_list_insert(commit, &process);
+
+    while(process) {
+        struct commit* com = pop_commit(&process);
+        if(com->object.flags & SEEN)
+            continue;
+
+        com->object.flags |= SEEN;
+        commit_list_insert(com, &ret);
+        struct commit_list* parents;
+
+        parse_commit(com);
+
+        for(parents = com->parents;
+            parents != NULL; parents = parents->next) {
+            struct commit* parent = parents->item;
+
+            parse_commit(parent);
+
+            if(!get_blob_sha1(parent->tree, pathname, sha1))
+                commit_list_insert(parent, &process);
+        }
+    }
+
+    return ret;
+}
+
+int main(int argc, const char **argv)
+{
+    unsigned char sha1[20];
+    struct commit *commit;
+    const char* filename;
+    int i;
+
+    setup_git_directory();
+
+    if (argc != 3)
+        die("Usage: blame commit-ish file");
+
+    if (get_sha1(argv[1], sha1))
+        die("get_sha1 failed");
+
+    commit = lookup_commit_reference(sha1);
+
+    filename = argv[2];
+
+    struct commit_list* list = get_commit_list(commit, filename);
+    sort_in_topological_order(&list, 1);
+
+    if(fill_util_info(commit, filename)) {
+        printf("%s not found in %s\n", filename, argv[1]);
+        return 0;
+    }
+    alloc_line_map(commit);
+
+    struct util_info* util = commit->object.util;
+    num_blame_lines = util->num_lines;
+    blame_lines = xmalloc(sizeof(struct commit*)*num_blame_lines);
+
+
+    for(i = 0; i < num_blame_lines; i++) {
+        blame_lines[i] = commit;
+
+        ((struct util_info*) commit->object.util)->line_map[i] = i;
+    }
+
+    process_commits(list, filename);
+
+    for(i = 0; i < num_blame_lines; i++) {
+        printf("%d %s\n", i+1-1, sha1_to_hex(blame_lines[i]->object.sha1));
+//        printf("%d %s\n", i+1-1, find_unique_abbrev(blame_lines[i]->object.sha1, 6));
+    }
+
+    if(DEBUG) {
+        printf("num get patch: %d\n", num_get_patch);
+        printf("num commits: %d\n", num_commits);
+    }
+
+    return 0;
+}
index 058a2aa..3ee3a0c 100644 (file)
@@ -3,11 +3,74 @@
  * The delta-parsing part is almost straight copy of patch-delta.c
  * which is (C) 2005 Nicolas Pitre <nico@cam.org>.
  */
+#include "cache.h"
+#include "delta.h"
+#include "count-delta.h"
 #include <stdlib.h>
 #include <string.h>
 #include <limits.h>
-#include "delta.h"
-#include "count-delta.h"
+
+struct span {
+       struct span *next;
+       unsigned long ofs;
+       unsigned long end;
+};
+
+static void touch_range(struct span **span,
+                       unsigned long ofs, unsigned long end)
+{
+       struct span *e = *span;
+       struct span *p = NULL;
+
+       while (e && e->ofs <= ofs) {
+               again:
+               if (ofs < e->end) {
+                       while (e->end < end) {
+                               if (e->next && e->next->ofs <= end) {
+                                       e->end = e->next->ofs;
+                                       e = e->next;
+                               }
+                               else {
+                                       e->end = end;
+                                       return;
+                               }
+                       }
+                       return;
+               }
+               p = e;
+               e = e->next;
+       }
+       if (e && e->ofs <= end) {
+               e->ofs = ofs;
+               goto again;
+       }
+       else {
+               e = xmalloc(sizeof(*e));
+               e->ofs = ofs;
+               e->end = end;
+               if (p) {
+                       e->next = p->next;
+                       p->next = e;
+               }
+               else {
+                       e->next = *span;
+                       *span = e;
+               }
+       }
+}
+
+static unsigned long count_range(struct span *s)
+{
+       struct span *t;
+       unsigned long sz = 0;
+       while (s) {
+               t = s;
+               sz += s->end - s->ofs;
+               s = s->next;
+               free(t);
+       }
+       return sz;
+}
 
 /*
  * NOTE.  We do not _interpret_ delta fully.  As an approximation, we
 int count_delta(void *delta_buf, unsigned long delta_size,
                unsigned long *src_copied, unsigned long *literal_added)
 {
-       unsigned long copied_from_source, added_literal;
+       unsigned long added_literal;
        const unsigned char *data, *top;
        unsigned char cmd;
        unsigned long src_size, dst_size, out;
+       struct span *span = NULL;
 
        if (delta_size < DELTA_SIZE_MIN)
                return -1;
@@ -35,7 +99,7 @@ int count_delta(void *delta_buf, unsigned long delta_size,
        src_size = get_delta_hdr_size(&data);
        dst_size = get_delta_hdr_size(&data);
 
-       added_literal = copied_from_source = out = 0;
+       added_literal = out = 0;
        while (data < top) {
                cmd = *data++;
                if (cmd & 0x80) {
@@ -49,7 +113,7 @@ int count_delta(void *delta_buf, unsigned long delta_size,
                        if (cmd & 0x40) cp_size |= (*data++ << 16);
                        if (cp_size == 0) cp_size = 0x10000;
 
-                       copied_from_source += cp_size;
+                       touch_range(&span, cp_off, cp_off+cp_size);
                        out += cp_size;
                } else {
                        /* write literal into dst */
@@ -59,6 +123,8 @@ int count_delta(void *delta_buf, unsigned long delta_size,
                }
        }
 
+       *src_copied = count_range(span);
+
        /* sanity check */
        if (data != top || out != dst_size)
                return -1;
@@ -66,7 +132,6 @@ int count_delta(void *delta_buf, unsigned long delta_size,
        /* delete size is what was _not_ copied from source.
         * edit size is that and literal additions.
         */
-       *src_copied = copied_from_source;
        *literal_added = added_literal;
        return 0;
 }
index c2f656a..2ed5984 100644 (file)
@@ -19,8 +19,9 @@
  */
 
 #include <stdlib.h>
+#include <string.h>
+#include <zlib.h>
 #include "delta.h"
-#include "zlib.h"
 
 
 /* block size: min = 16, max = 64k, power of 2 */
 #define MIN(a, b) ((a) < (b) ? (a) : (b))
 
 #define GR_PRIME 0x9e370001
-#define HASH(v, b) (((unsigned int)(v) * GR_PRIME) >> (32 - (b)))
-       
-static unsigned int hashbits(unsigned int size)
-{
-       unsigned int val = 1, bits = 0;
-       while (val < size && bits < 32) {
-               val <<= 1;
-               bits++;
-       }
-       return bits ? bits: 1;
-}
-
-typedef struct s_chanode {
-       struct s_chanode *next;
-       int icurr;
-} chanode_t;
-
-typedef struct s_chastore {
-       int isize, nsize;
-       chanode_t *ancur;
-} chastore_t;
-
-static void cha_init(chastore_t *cha, int isize, int icount)
-{
-       cha->isize = isize;
-       cha->nsize = icount * isize;
-       cha->ancur = NULL;
-}
-
-static void *cha_alloc(chastore_t *cha)
-{
-       chanode_t *ancur;
-       void *data;
+#define HASH(v, shift) (((unsigned int)(v) * GR_PRIME) >> (shift))
 
-       ancur = cha->ancur;
-       if (!ancur || ancur->icurr == cha->nsize) {
-               ancur = malloc(sizeof(chanode_t) + cha->nsize);
-               if (!ancur)
-                       return NULL;
-               ancur->icurr = 0;
-               ancur->next = cha->ancur;
-               cha->ancur = ancur;
-       }
-
-       data = (void *)ancur + sizeof(chanode_t) + ancur->icurr;
-       ancur->icurr += cha->isize;
-       return data;
-}
-
-static void cha_free(chastore_t *cha)
-{
-       chanode_t *cur = cha->ancur;
-       while (cur) {
-               chanode_t *tmp = cur;
-               cur = cur->next;
-               free(tmp);
-       }
-}
-
-typedef struct s_bdrecord {
-       struct s_bdrecord *next;
-       unsigned int fp;
+struct index {
        const unsigned char *ptr;
-} bdrecord_t;
-
-typedef struct s_bdfile {
-       chastore_t cha;
-       unsigned int fphbits;
-       bdrecord_t **fphash;
-} bdfile_t;
+       unsigned int val;
+       struct index *next;
+};
 
-static int delta_prepare(const unsigned char *buf, int bufsize, bdfile_t *bdf)
+static struct index ** delta_index(const unsigned char *buf,
+                                  unsigned long bufsize,
+                                  unsigned int *hash_shift)
 {
-       unsigned int fphbits;
-       int i, hsize;
-       const unsigned char *data, *top;
-       bdrecord_t *brec;
-       bdrecord_t **fphash;
-
-       fphbits = hashbits(bufsize / BLK_SIZE + 1);
-       hsize = 1 << fphbits;
-       fphash = malloc(hsize * sizeof(bdrecord_t *));
-       if (!fphash)
-               return -1;
-       for (i = 0; i < hsize; i++)
-               fphash[i] = NULL;
-       cha_init(&bdf->cha, sizeof(bdrecord_t), hsize / 4 + 1);
-
-       top = buf + bufsize;
-       data = buf + (bufsize / BLK_SIZE) * BLK_SIZE;
-       if (data == top)
+       unsigned int hsize, hshift, entries, blksize, i;
+       const unsigned char *data;
+       struct index *entry, **hash;
+       void *mem;
+
+       /* determine index hash size */
+       entries = (bufsize + BLK_SIZE - 1) / BLK_SIZE;
+       hsize = entries / 4;
+       for (i = 4; (1 << i) < hsize && i < 16; i++);
+       hsize = 1 << i;
+       hshift = 32 - i;
+       *hash_shift = hshift;
+
+       /* allocate lookup index */
+       mem = malloc(hsize * sizeof(*hash) + entries * sizeof(*entry));
+       if (!mem)
+               return NULL;
+       hash = mem;
+       entry = mem + hsize * sizeof(*hash);
+       memset(hash, 0, hsize * sizeof(*hash));
+
+       /* then populate it */
+       data = buf + entries * BLK_SIZE - BLK_SIZE;
+       blksize = bufsize - (data - buf);
+       while (data >= buf) {
+               unsigned int val = adler32(0, data, blksize);
+               i = HASH(val, hshift);
+               entry->ptr = data;
+               entry->val = val;
+               entry->next = hash[i];
+               hash[i] = entry++;
+               blksize = BLK_SIZE;
                data -= BLK_SIZE;
+       }
 
-       for ( ; data >= buf; data -= BLK_SIZE) {
-               brec = cha_alloc(&bdf->cha);
-               if (!brec) {
-                       cha_free(&bdf->cha);
-                       free(fphash);
-                       return -1;
-               }
-               brec->fp = adler32(0, data, MIN(BLK_SIZE, top - data));
-               brec->ptr = data;
-               i = HASH(brec->fp, fphbits);
-               brec->next = fphash[i];
-               fphash[i] = brec;
-       }
-
-       bdf->fphbits = fphbits;
-       bdf->fphash = fphash;
-
-       return 0;
-}
-
-static void delta_cleanup(bdfile_t *bdf)
-{
-       free(bdf->fphash);
-       cha_free(&bdf->cha);
+       return hash;
 }
 
+/* provide the size of the copy opcode given the block offset and size */
 #define COPYOP_SIZE(o, s) \
     (!!(o & 0xff) + !!(o & 0xff00) + !!(o & 0xff0000) + !!(o & 0xff000000) + \
      !!(s & 0xff) + !!(s & 0xff00) + 1)
 
+/* the maximum size for any opcode */
+#define MAX_OP_SIZE COPYOP_SIZE(0xffffffff, 0xffffffff)
+
 void *diff_delta(void *from_buf, unsigned long from_size,
                 void *to_buf, unsigned long to_size,
                 unsigned long *delta_size,
                 unsigned long max_size)
 {
-       int i, outpos, outsize, inscnt, csize, msize, moff;
-       unsigned int fp;
-       const unsigned char *ref_data, *ref_top, *data, *top, *ptr1, *ptr2;
-       unsigned char *out, *orig;
-       bdrecord_t *brec;
-       bdfile_t bdf;
+       unsigned int i, outpos, outsize, inscnt, hash_shift;
+       const unsigned char *ref_data, *ref_top, *data, *top;
+       unsigned char *out;
+       struct index *entry, **hash;
 
-       if (!from_size || !to_size || delta_prepare(from_buf, from_size, &bdf))
+       if (!from_size || !to_size)
+               return NULL;
+       hash = delta_index(from_buf, from_size, &hash_shift);
+       if (!hash)
                return NULL;
-       
+
        outpos = 0;
        outsize = 8192;
+       if (max_size && outsize >= max_size)
+               outsize = max_size + MAX_OP_SIZE + 1;
        out = malloc(outsize);
        if (!out) {
-               delta_cleanup(&bdf);
+               free(hash);
                return NULL;
        }
 
@@ -199,28 +138,32 @@ void *diff_delta(void *from_buf, unsigned long from_size,
        }
 
        inscnt = 0;
-       moff = 0;
-       while (data < top) {
-               msize = 0;
-               fp = adler32(0, data, MIN(top - data, BLK_SIZE));
-               i = HASH(fp, bdf.fphbits);
-               for (brec = bdf.fphash[i]; brec; brec = brec->next) {
-                       if (brec->fp == fp) {
-                               csize = ref_top - brec->ptr;
-                               if (csize > top - data)
-                                       csize = top - data;
-                               for (ptr1 = brec->ptr, ptr2 = data; 
-                                    csize && *ptr1 == *ptr2;
-                                    csize--, ptr1++, ptr2++);
 
-                               csize = ptr1 - brec->ptr;
-                               if (csize > msize) {
-                                       moff = brec->ptr - ref_data;
-                                       msize = csize;
-                                       if (msize >= 0x10000) {
-                                               msize = 0x10000;
-                                               break;
-                                       }
+       while (data < top) {
+               unsigned int moff = 0, msize = 0;
+               unsigned int blksize = MIN(top - data, BLK_SIZE);
+               unsigned int val = adler32(0, data, blksize);
+               i = HASH(val, hash_shift);
+               for (entry = hash[i]; entry; entry = entry->next) {
+                       const unsigned char *ref = entry->ptr;
+                       const unsigned char *src = data;
+                       unsigned int ref_size = ref_top - ref;
+                       if (entry->val != val)
+                               continue;
+                       if (ref_size > top - src)
+                               ref_size = top - src;
+                       while (ref_size && *src++ == *ref) {
+                               ref++;
+                               ref_size--;
+                       }
+                       ref_size = ref - entry->ptr;
+                       if (ref_size > msize) {
+                               /* this is our best match so far */
+                               moff = entry->ptr - ref_data;
+                               msize = ref_size;
+                               if (msize >= 0x10000) {
+                                       msize = 0x10000;
+                                       break;
                                }
                        }
                }
@@ -235,13 +178,15 @@ void *diff_delta(void *from_buf, unsigned long from_size,
                                inscnt = 0;
                        }
                } else {
+                       unsigned char *op;
+
                        if (inscnt) {
                                out[outpos - inscnt - 1] = inscnt;
                                inscnt = 0;
                        }
 
                        data += msize;
-                       orig = out + outpos++;
+                       op = out + outpos++;
                        i = 0x80;
 
                        if (moff & 0xff) { out[outpos++] = moff; i |= 0x01; }
@@ -256,23 +201,21 @@ void *diff_delta(void *from_buf, unsigned long from_size,
                        msize >>= 8;
                        if (msize & 0xff) { out[outpos++] = msize; i |= 0x20; }
 
-                       *orig = i;
-               }
-
-               if (max_size && outpos > max_size) {
-                       free(out);
-                       delta_cleanup(&bdf);
-                       return NULL;
+                       *op = i;
                }
 
-               /* next time around the largest possible output is 1 + 4 + 3 */
-               if (outpos > outsize - 8) {
+               if (outpos >= outsize - MAX_OP_SIZE) {
                        void *tmp = out;
                        outsize = outsize * 3 / 2;
-                       out = realloc(out, outsize);
+                       if (max_size && outsize >= max_size)
+                               outsize = max_size + MAX_OP_SIZE + 1;
+                       if (max_size && outpos > max_size)
+                               out = NULL;
+                       else
+                               out = realloc(out, outsize);
                        if (!out) {
                                free(tmp);
-                               delta_cleanup(&bdf);
+                               free(hash);
                                return NULL;
                        }
                }
@@ -281,7 +224,7 @@ void *diff_delta(void *from_buf, unsigned long from_size,
        if (inscnt)
                out[outpos - inscnt - 1] = inscnt;
 
-       delta_cleanup(&bdf);
+       free(hash);
        *delta_size = outpos;
        return out;
 }
index 12cd816..91d6c63 100644 (file)
@@ -18,7 +18,7 @@
 #define MAX_SCORE 60000.0
 #define DEFAULT_RENAME_SCORE 30000 /* rename/copy similarity minimum (50%) */
 #define DEFAULT_BREAK_SCORE  30000 /* minimum for break to happen (50%)*/
-#define DEFAULT_MERGE_SCORE  48000 /* maximum for break-merge to happen (80%)*/
+#define DEFAULT_MERGE_SCORE  45000 /* maximum for break-merge to happen (75%)*/
 
 #define MINIMUM_BREAK_SIZE     400 /* do not break a file smaller than this */