correct usage help string for git-hash-object

diff --git a/index-pack.c b/index-pack.c
index 25db5db24b239409657510e8c2eeb3845b374bbf..52064befdbbbdf671bd08e369a133d4f1fee03c1 100644 (file)
--- a/index-pack.c
+++ b/index-pack.c
@@ -10,7 +10,7 @@
 #include "fsck.h"
 
 static const char index_pack_usage[] =
-"git-index-pack [-v] [-o <index-file>] [{ ---keep | --keep=<msg> }] [--strict] { <pack-file> | --stdin [--fix-thin] [<pack-file>] }";
+"git index-pack [-v] [-o <index-file>] [{ ---keep | --keep=<msg> }] [--strict] { <pack-file> | --stdin [--fix-thin] [<pack-file>] }";
 
 struct object_entry
 {
@@ -26,6 +26,14 @@ union delta_base {
        off_t offset;
 };
 
+struct base_data {
+       struct base_data *base;
+       struct base_data *child;
+       struct object_entry *obj;
+       void *data;
+       unsigned long size;
+};
+
 /*
  * Even if sizeof(union delta_base) == 24 on 64-bit archs, we really want
  * to memcmp() only the first 20 bytes.
@@ -43,6 +51,8 @@ struct delta_entry
 
 static struct object_entry *objects;
 static struct delta_entry *deltas;
+static struct base_data *base_cache;
+static size_t base_cache_used;
 static int nr_objects;
 static int nr_deltas;
 static int nr_resolved_deltas;
@@ -211,6 +221,46 @@ static void bad_object(unsigned long offset, const char *format, ...)
        die("pack has bad object at offset %lu: %s", offset, buf);
 }
 
+static void prune_base_data(struct base_data *retain)
+{
+       struct base_data *b = base_cache;
+       for (b = base_cache;
+            base_cache_used > delta_base_cache_limit && b;
+            b = b->child) {
+               if (b->data && b != retain) {
+                       free(b->data);
+                       b->data = NULL;
+                       base_cache_used -= b->size;
+               }
+       }
+}
+
+static void link_base_data(struct base_data *base, struct base_data *c)
+{
+       if (base)
+               base->child = c;
+       else
+               base_cache = c;
+
+       c->base = base;
+       c->child = NULL;
+       base_cache_used += c->size;
+       prune_base_data(c);
+}
+
+static void unlink_base_data(struct base_data *c)
+{
+       struct base_data *base = c->base;
+       if (base)
+               base->child = NULL;
+       else
+               base_cache = NULL;
+       if (c->data) {
+               free(c->data);
+               base_cache_used -= c->size;
+       }
+}
+
 static void *unpack_entry_data(unsigned long offset, unsigned long size)
 {
        z_stream stream;
@@ -426,33 +476,60 @@ static void sha1_object(const void *data, unsigned long size,
        }
 }
 
-static void resolve_delta(struct object_entry *delta_obj, void *base_data,
-                         unsigned long base_size, enum object_type type)
+static void *get_base_data(struct base_data *c)
+{
+       if (!c->data) {
+               struct object_entry *obj = c->obj;
+
+               if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) {
+                       void *base = get_base_data(c->base);
+                       void *raw = get_data_from_pack(obj);
+                       c->data = patch_delta(
+                               base, c->base->size,
+                               raw, obj->size,
+                               &c->size);
+                       free(raw);
+                       if (!c->data)
+                               bad_object(obj->idx.offset, "failed to apply delta");
+               } else
+                       c->data = get_data_from_pack(obj);
+
+               base_cache_used += c->size;
+               prune_base_data(c);
+       }
+       return c->data;
+}
+
+static void resolve_delta(struct object_entry *delta_obj,
+                         struct base_data *base_obj, enum object_type type)
 {
        void *delta_data;
        unsigned long delta_size;
-       void *result;
-       unsigned long result_size;
        union delta_base delta_base;
        int j, first, last;
+       struct base_data result;
 
        delta_obj->real_type = type;
        delta_data = get_data_from_pack(delta_obj);
        delta_size = delta_obj->size;
-       result = patch_delta(base_data, base_size, delta_data, delta_size,
-                            &result_size);
+       result.data = patch_delta(get_base_data(base_obj), base_obj->size,
+                            delta_data, delta_size,
+                            &result.size);
        free(delta_data);
-       if (!result)
+       if (!result.data)
                bad_object(delta_obj->idx.offset, "failed to apply delta");
-       sha1_object(result, result_size, type, delta_obj->idx.sha1);
+       sha1_object(result.data, result.size, type, delta_obj->idx.sha1);
        nr_resolved_deltas++;
 
+       result.obj = delta_obj;
+       link_base_data(base_obj, &result);
+
        hashcpy(delta_base.sha1, delta_obj->idx.sha1);
        if (!find_delta_children(&delta_base, &first, &last)) {
                for (j = first; j <= last; j++) {
                        struct object_entry *child = objects + deltas[j].obj_no;
                        if (child->real_type == OBJ_REF_DELTA)
-                               resolve_delta(child, result, result_size, type);
+                               resolve_delta(child, &result, type);
                }
        }
 
@@ -462,11 +539,11 @@ static void resolve_delta(struct object_entry *delta_obj, void *base_data,
                for (j = first; j <= last; j++) {
                        struct object_entry *child = objects + deltas[j].obj_no;
                        if (child->real_type == OBJ_OFS_DELTA)
-                               resolve_delta(child, result, result_size, type);
+                               resolve_delta(child, &result, type);
                }
        }
 
-       free(result);
+       unlink_base_data(&result);
 }
 
 static int compare_delta_entry(const void *a, const void *b)
@@ -481,7 +558,6 @@ static void parse_pack_objects(unsigned char *sha1)
 {
        int i;
        struct delta_entry *delta = deltas;
-       void *data;
        struct stat st;
 
        /*
@@ -496,7 +572,7 @@ static void parse_pack_objects(unsigned char *sha1)
                                nr_objects);
        for (i = 0; i < nr_objects; i++) {
                struct object_entry *obj = &objects[i];
-               data = unpack_raw_entry(obj, &delta->base);
+               void *data = unpack_raw_entry(obj, &delta->base);
                obj->real_type = obj->type;
                if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA) {
                        nr_deltas++;
@@ -545,6 +621,7 @@ static void parse_pack_objects(unsigned char *sha1)
                struct object_entry *obj = &objects[i];
                union delta_base base;
                int j, ref, ref_first, ref_last, ofs, ofs_first, ofs_last;
+               struct base_data base_obj;
 
                if (obj->type == OBJ_REF_DELTA || obj->type == OBJ_OFS_DELTA)
                        continue;
@@ -555,22 +632,24 @@ static void parse_pack_objects(unsigned char *sha1)
                ofs = !find_delta_children(&base, &ofs_first, &ofs_last);
                if (!ref && !ofs)
                        continue;
-               data = get_data_from_pack(obj);
+               base_obj.data = get_data_from_pack(obj);
+               base_obj.size = obj->size;
+               base_obj.obj = obj;
+               link_base_data(NULL, &base_obj);
+
                if (ref)
                        for (j = ref_first; j <= ref_last; j++) {
                                struct object_entry *child = objects + deltas[j].obj_no;
                                if (child->real_type == OBJ_REF_DELTA)
-                                       resolve_delta(child, data,
-                                                     obj->size, obj->type);
+                                       resolve_delta(child, &base_obj, obj->type);
                        }
                if (ofs)
                        for (j = ofs_first; j <= ofs_last; j++) {
                                struct object_entry *child = objects + deltas[j].obj_no;
                                if (child->real_type == OBJ_OFS_DELTA)
-                                       resolve_delta(child, data,
-                                                     obj->size, obj->type);
+                                       resolve_delta(child, &base_obj, obj->type);
                        }
-               free(data);
+               unlink_base_data(&base_obj);
                display_progress(progress, nr_resolved_deltas);
        }
 }
@@ -601,7 +680,8 @@ static int write_compressed(int fd, void *in, unsigned int size, uint32_t *obj_c
        return size;
 }
 
-static void append_obj_to_pack(const unsigned char *sha1, void *buf,
+static struct object_entry *append_obj_to_pack(
+                              const unsigned char *sha1, void *buf,
                               unsigned long size, enum object_type type)
 {
        struct object_entry *obj = &objects[nr_objects++];
@@ -619,9 +699,14 @@ static void append_obj_to_pack(const unsigned char *sha1, void *buf,
        write_or_die(output_fd, header, n);
        obj[0].idx.crc32 = crc32(0, Z_NULL, 0);
        obj[0].idx.crc32 = crc32(obj[0].idx.crc32, header, n);
+       obj[0].size = size;
+       obj[0].hdr_size = n;
+       obj[0].type = type;
+       obj[0].real_type = type;
        obj[1].idx.offset = obj[0].idx.offset + n;
        obj[1].idx.offset += write_compressed(output_fd, buf, size, &obj[0].idx.crc32);
        hashcpy(obj->idx.sha1, sha1);
+       return obj;
 }
 
 static int delta_pos_compare(const void *_a, const void *_b)
@@ -656,28 +741,31 @@ static void fix_unresolved_deltas(int nr_unresolved)
 
        for (i = 0; i < n; i++) {
                struct delta_entry *d = sorted_by_pos[i];
-               void *data;
-               unsigned long size;
                enum object_type type;
                int j, first, last;
+               struct base_data base_obj;
 
                if (objects[d->obj_no].real_type != OBJ_REF_DELTA)
                        continue;
-               data = read_sha1_file(d->base.sha1, &type, &size);
-               if (!data)
+               base_obj.data = read_sha1_file(d->base.sha1, &type, &base_obj.size);
+               if (!base_obj.data)
                        continue;
 
+               if (check_sha1_signature(d->base.sha1, base_obj.data,
+                               base_obj.size, typename(type)))
+                       die("local object %s is corrupt", sha1_to_hex(d->base.sha1));
+               base_obj.obj = append_obj_to_pack(d->base.sha1, base_obj.data,
+                       base_obj.size, type);
+               link_base_data(NULL, &base_obj);
+
                find_delta_children(&d->base, &first, &last);
                for (j = first; j <= last; j++) {
                        struct object_entry *child = objects + deltas[j].obj_no;
                        if (child->real_type == OBJ_REF_DELTA)
-                               resolve_delta(child, data, size, type);
+                               resolve_delta(child, &base_obj, type);
                }
 
-               if (check_sha1_signature(d->base.sha1, data, size, typename(type)))
-                       die("local object %s is corrupt", sha1_to_hex(d->base.sha1));
-               append_obj_to_pack(d->base.sha1, data, size, type);
-               free(data);
+               unlink_base_data(&base_obj);
                display_progress(progress, nr_resolved_deltas);
        }
        free(sorted_by_pos);