[2/5] Implementations of parsing functions
This implements the parsing functions.
Signed-Off-By: Daniel Barkalow <barkalow@iabervon.org>
Index: blob.c
===================================================================
--- /dev/null (tree:5ca133e1b74aee39b2124c0ec9fd51539babb5e0)
+++ 1172a9b8f45b2fd640985595cc5258db3b027828/blob.c (mode:100644 sha1:04e0c1da9b1f4cdb1d1c5881b785babd3b0ceb09)
@@ -0,0 +1,24 @@
+#include "blob.h"
+#include "cache.h"
+#include <stdlib.h>
+
+const char *blob_type = "blob";
+
+struct blob *lookup_blob(unsigned char *sha1)
+{
+ struct object *obj = lookup_object(sha1);
+ if (!obj) {
+ struct blob *ret = malloc(sizeof(struct blob));
+ bzero(ret, sizeof(struct blob));
+ created_object(sha1, &ret->object);
+ ret->object.type = blob_type;
+ ret->object.parsed = 1;
+ return ret;
+ }
+ if (obj->parsed && obj->type != blob_type) {
+ error("Object %s is a %s, not a blob",
+ sha1_to_hex(sha1), obj->type);
+ return NULL;
+ }
+ return (struct blob *) obj;
+}
Index: commit.c
===================================================================
--- /dev/null (tree:5ca133e1b74aee39b2124c0ec9fd51539babb5e0)
+++ 1172a9b8f45b2fd640985595cc5258db3b027828/commit.c (mode:100644 sha1:0099baa63971d86ee30ef2a7da25057f0f45a964)
@@ -0,0 +1,85 @@
+#include "commit.h"
+#include "cache.h"
+#include <string.h>
+
+const char *commit_type = "commit";
+
+struct commit *lookup_commit(unsigned char *sha1)
+{
+ struct object *obj = lookup_object(sha1);
+ if (!obj) {
+ struct commit *ret = malloc(sizeof(struct commit));
+ bzero(ret, sizeof(struct commit));
+ created_object(sha1, &ret->object);
+ return ret;
+ }
+ if (obj->parsed && obj->type != commit_type) {
+ error("Object %s is a %s, not a commit",
+ sha1_to_hex(sha1), obj->type);
+ return NULL;
+ }
+ return (struct commit *) obj;
+}
+
+static unsigned long parse_commit_date(const char *buf)
+{
+ unsigned long date;
+
+ if (memcmp(buf, "author", 6))
+ return 0;
+ while (*buf++ != '\n')
+ /* nada */;
+ if (memcmp(buf, "committer", 9))
+ return 0;
+ while (*buf++ != '>')
+ /* nada */;
+ date = strtoul(buf, NULL, 10);
+ if (date == ULONG_MAX)
+ date = 0;
+ return date;
+}
+
+int parse_commit(struct commit *item)
+{
+ char type[20];
+ void * buffer, *bufptr;
+ unsigned long size;
+ unsigned char parent[20];
+ if (item->object.parsed)
+ return 0;
+ item->object.parsed = 1;
+ buffer = bufptr = read_sha1_file(item->object.sha1, type, &size);
+ if (!buffer)
+ return error("Could not read %s",
+ sha1_to_hex(item->object.sha1));
+ if (strcmp(type, commit_type))
+ return error("Object %s not a commit",
+ sha1_to_hex(item->object.sha1));
+ item->object.type = commit_type;
+ get_sha1_hex(bufptr + 5, parent);
+ item->tree = lookup_tree(parent);
+ add_ref(&item->object, &item->tree->object);
+ bufptr += 46; /* "tree " + "hex sha1" + "\n" */
+ while (!memcmp(bufptr, "parent ", 7) &&
+ !get_sha1_hex(bufptr + 7, parent)) {
+ struct commit_list *new_parent =
+ malloc(sizeof(struct commit_list));
+ new_parent->next = item->parents;
+ new_parent->item = lookup_commit(parent);
+ add_ref(&item->object, &new_parent->item->object);
+ item->parents = new_parent;
+ bufptr += 48;
+ }
+ item->date = parse_commit_date(bufptr);
+ free(buffer);
+ return 0;
+}
+
+void free_commit_list(struct commit_list *list)
+{
+ while (list) {
+ struct commit_list *temp = list;
+ list = temp->next;
+ free(temp);
+ }
+}
Index: object.c
===================================================================
--- /dev/null (tree:5ca133e1b74aee39b2124c0ec9fd51539babb5e0)
+++ 1172a9b8f45b2fd640985595cc5258db3b027828/object.c (mode:100644 sha1:986624ac7a7fd9229e05e1f181fd500640298d9e)
@@ -0,0 +1,96 @@
+#include "object.h"
+#include "cache.h"
+#include <stdlib.h>
+#include <string.h>
+
+struct object **objs;
+int nr_objs;
+static int obj_allocs;
+
+static int find_object(unsigned char *sha1)
+{
+ int first = 0, last = nr_objs;
+
+ while (first < last) {
+ int next = (first + last) / 2;
+ struct object *obj = objs[next];
+ int cmp;
+
+ cmp = memcmp(sha1, obj->sha1, 20);
+ if (!cmp)
+ return next;
+ if (cmp < 0) {
+ last = next;
+ continue;
+ }
+ first = next+1;
+ }
+ return -first-1;
+}
+
+struct object *lookup_object(unsigned char *sha1)
+{
+ int pos = find_object(sha1);
+ if (pos >= 0)
+ return objs[pos];
+ return NULL;
+}
+
+void created_object(unsigned char *sha1, struct object *obj)
+{
+ int pos = find_object(sha1);
+
+ obj->parsed = 0;
+ memcpy(obj->sha1, sha1, 20);
+ obj->type = NULL;
+ obj->refs = NULL;
+ obj->used = 0;
+
+ if (pos >= 0)
+ die("Inserting %s twice\n", sha1_to_hex(sha1));
+ pos = -pos-1;
+
+ if (obj_allocs == nr_objs) {
+ obj_allocs = alloc_nr(obj_allocs);
+ objs = realloc(objs, obj_allocs * sizeof(struct object *));
+ }
+
+ /* Insert it into the right place */
+ memmove(objs + pos + 1, objs + pos, (nr_objs - pos) *
+ sizeof(struct object *));
+
+ objs[pos] = obj;
+ nr_objs++;
+}
+
+void add_ref(struct object *refer, struct object *target)
+{
+ struct object_list **pp = &refer->refs;
+ struct object_list *p;
+
+ while ((p = *pp) != NULL) {
+ if (p->item == target)
+ return;
+ pp = &p->next;
+ }
+
+ target->used = 1;
+ p = malloc(sizeof(*p));
+ p->item = target;
+ p->next = NULL;
+ *pp = p;
+}
+
+void mark_reachable(struct object *obj, unsigned int mask)
+{
+ struct object_list *p = obj->refs;
+
+ /* If we've been here already, don't bother */
+ if (obj->flags & mask)
+ return;
+ obj->flags |= mask;
+ while (p) {
+ mark_reachable(p->item, mask);
+ p = p->next;
+ }
+}
Index: tree.c
===================================================================
--- /dev/null (tree:5ca133e1b74aee39b2124c0ec9fd51539babb5e0)
+++ 1172a9b8f45b2fd640985595cc5258db3b027828/tree.c (mode:100644 sha1:7c5e5e46f4967b0812b06c0114946c3a6432c8d8)
@@ -0,0 +1,67 @@
+#include "tree.h"
+#include "blob.h"
+#include "cache.h"
+#include <stdlib.h>
+
+const char *tree_type = "tree";
+
+struct tree *lookup_tree(unsigned char *sha1)
+{
+ struct object *obj = lookup_object(sha1);
+ if (!obj) {
+ struct tree *ret = malloc(sizeof(struct tree));
+ bzero(ret, sizeof(struct tree));
+ created_object(sha1, &ret->object);
+ return ret;
+ }
+ if (obj->parsed && obj->type != tree_type) {
+ error("Object %s is a %s, not a tree",
+ sha1_to_hex(sha1), obj->type);
+ return NULL;
+ }
+ return (struct tree *) obj;
+}
+
+int parse_tree(struct tree *item)
+{
+ char type[20];
+ void *buffer, *bufptr;
+ unsigned long size;
+ if (item->object.parsed)
+ return 0;
+ item->object.parsed = 1;
+ item->object.type = tree_type;
+ buffer = bufptr = read_sha1_file(item->object.sha1, type, &size);
+ if (!buffer)
+ return error("Could not read %s",
+ sha1_to_hex(item->object.sha1));
+ if (strcmp(type, tree_type))
+ return error("Object %s not a tree",
+ sha1_to_hex(item->object.sha1));
+ while (size) {
+ struct object *obj;
+ int len = 1+strlen(bufptr);
+ unsigned char *file_sha1 = bufptr + len;
+ char *path = strchr(bufptr, ' ');
+ unsigned int mode;
+ if (size < len + 20 || !path ||
+ sscanf(bufptr, "%o", &mode) != 1)
+ return -1;
+
+ /* Warn about trees that don't do the recursive thing.. */
+ if (strchr(path, '/')) {
+ item->has_full_path = 1;
+ }
+
+ bufptr += len + 20;
+ size -= len + 20;
+
+ if (S_ISDIR(mode)) {
+ obj = &lookup_tree(file_sha1)->object;
+ } else {
+ obj = &lookup_blob(file_sha1)->object;
+ }
+ add_ref(&item->object, obj);
+ }
+ return 0;
+}
Daniel Barkalow <barkalow@iabervon.org>