Fix crash when reading the empty tree
[gitweb.git] / tree.c
diff --git a/tree.c b/tree.c
index e988aed6a85d15568dcb93b69035b97a24e30cc9..d599fb5e1a8b689460c1e53b319f88aeda9a4c89 100644 (file)
--- a/tree.c
+++ b/tree.c
+#include "cache.h"
 #include "tree.h"
 #include "blob.h"
-#include "cache.h"
+#include "commit.h"
+#include "tag.h"
 #include <stdlib.h>
 
 const char *tree_type = "tree";
 
 static int read_one_entry(unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage)
 {
-       int len = strlen(pathname);
-       unsigned int size = cache_entry_size(baselen + len);
-       struct cache_entry *ce = malloc(size);
+       int len;
+       unsigned int size;
+       struct cache_entry *ce;
 
-       memset(ce, 0, size);
+       if (S_ISDIR(mode))
+               return READ_TREE_RECURSIVE;
+
+       len = strlen(pathname);
+       size = cache_entry_size(baselen + len);
+       ce = xcalloc(1, size);
 
        ce->ce_mode = create_ce_mode(mode);
        ce->ce_flags = create_ce_flags(baselen + len, stage);
        memcpy(ce->name, base, baselen);
        memcpy(ce->name + baselen, pathname, len+1);
        memcpy(ce->sha1, sha1, 20);
-       return add_cache_entry(ce, 1);
+       return add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
 }
 
-static int read_tree_recursive(void *buffer, unsigned long size,
-                              const char *base, int baselen, int stage)
+static int match_tree_entry(const char *base, int baselen, const char *path, unsigned int mode, const char **paths)
 {
-       while (size) {
-               int len = strlen(buffer)+1;
-               unsigned char *sha1 = buffer + len;
-               char *path = strchr(buffer, ' ')+1;
-               unsigned int mode;
+       const char *match;
+       int pathlen;
 
-               if (size < len + 20 || sscanf(buffer, "%o", &mode) != 1)
-                       return -1;
+       if (!paths)
+               return 1;
+       pathlen = strlen(path);
+       while ((match = *paths++) != NULL) {
+               int matchlen = strlen(match);
 
-               buffer = sha1 + 20;
-               size -= len + 20;
+               if (baselen >= matchlen) {
+                       /* If it doesn't match, move along... */
+                       if (strncmp(base, match, matchlen))
+                               continue;
+                       /* The base is a subdirectory of a path which was specified. */
+                       return 1;
+               }
+
+               /* Does the base match? */
+               if (strncmp(base, match, baselen))
+                       continue;
+
+               match += baselen;
+               matchlen -= baselen;
+
+               if (pathlen > matchlen)
+                       continue;
+
+               if (matchlen > pathlen) {
+                       if (match[pathlen] != '/')
+                               continue;
+                       if (!S_ISDIR(mode))
+                               continue;
+               }
 
-               if (S_ISDIR(mode)) {
+               if (strncmp(path, match, pathlen))
+                       continue;
+
+               return 1;
+       }
+       return 0;
+}
+
+int read_tree_recursive(struct tree *tree,
+                       const char *base, int baselen,
+                       int stage, const char **match,
+                       read_tree_fn_t fn)
+{
+       struct tree_entry_list *list;
+       if (parse_tree(tree))
+               return -1;
+       list = tree->entries;
+       while (list) {
+               struct tree_entry_list *current = list;
+               list = list->next;
+               if (!match_tree_entry(base, baselen, current->name,
+                                     current->mode, match))
+                       continue;
+
+               switch (fn(current->item.any->sha1, base, baselen,
+                          current->name, current->mode, stage)) {
+               case 0:
+                       continue;
+               case READ_TREE_RECURSIVE:
+                       break;;
+               default:
+                       return -1;
+               }
+               if (current->directory) {
                        int retval;
-                       int pathlen = strlen(path);
-                       char *newbase = malloc(baselen + 1 + pathlen);
-                       void *eltbuf;
-                       char elttype[20];
-                       unsigned long eltsize;
-
-                       eltbuf = read_sha1_file(sha1, elttype, &eltsize);
-                       if (!eltbuf || strcmp(elttype, "tree"))
-                               return -1;
+                       int pathlen = strlen(current->name);
+                       char *newbase;
+
+                       newbase = xmalloc(baselen + 1 + pathlen);
                        memcpy(newbase, base, baselen);
-                       memcpy(newbase + baselen, path, pathlen);
+                       memcpy(newbase + baselen, current->name, pathlen);
                        newbase[baselen + pathlen] = '/';
-                       retval = read_tree_recursive(eltbuf, eltsize,
+                       retval = read_tree_recursive(current->item.tree,
                                                     newbase,
-                                                    baselen + pathlen + 1, stage);
-                       free(eltbuf);
+                                                    baselen + pathlen + 1,
+                                                    stage, match, fn);
                        free(newbase);
                        if (retval)
                                return -1;
                        continue;
                }
-               if (read_one_entry(sha1, base, baselen, path, mode, stage) < 0)
-                       return -1;
        }
        return 0;
 }
 
-int read_tree(void *buffer, unsigned long size, int stage)
+int read_tree(struct tree *tree, int stage, const char **match)
 {
-       return read_tree_recursive(buffer, size, "", 0, stage);
+       return read_tree_recursive(tree, "", 0, stage, match, read_one_entry);
 }
 
-struct tree *lookup_tree(unsigned char *sha1)
+struct tree *lookup_tree(const unsigned char *sha1)
 {
        struct object *obj = lookup_object(sha1);
        if (!obj) {
-               struct tree *ret = malloc(sizeof(struct tree));
-               memset(ret, 0, sizeof(struct tree));
+               struct tree *ret = xcalloc(1, sizeof(struct tree));
                created_object(sha1, &ret->object);
+               ret->object.type = tree_type;
                return ret;
        }
-       if (obj->parsed && obj->type != tree_type) {
+       if (!obj->type)
+               obj->type = tree_type;
+       if (obj->type != tree_type) {
                error("Object %s is a %s, not a tree", 
                      sha1_to_hex(sha1), obj->type);
                return NULL;
@@ -87,24 +143,19 @@ struct tree *lookup_tree(unsigned char *sha1)
        return (struct tree *) obj;
 }
 
-int parse_tree(struct tree *item)
+int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
 {
-       char type[20];
-       void *buffer, *bufptr;
-       unsigned long size;
+       void *bufptr = buffer;
+       struct tree_entry_list **list_p;
+       int n_refs = 0;
+
        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));
+       list_p = &item->entries;
        while (size) {
                struct object *obj;
+               struct tree_entry_list *entry;
                int len = 1+strlen(bufptr);
                unsigned char *file_sha1 = bufptr + len;
                char *path = strchr(bufptr, ' ');
@@ -113,20 +164,81 @@ int parse_tree(struct tree *item)
                    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;
-               }
+               entry = xmalloc(sizeof(struct tree_entry_list));
+               entry->name = strdup(path + 1);
+               entry->directory = S_ISDIR(mode) != 0;
+               entry->executable = (mode & S_IXUSR) != 0;
+               entry->symlink = S_ISLNK(mode) != 0;
+               entry->zeropad = *(char *)bufptr == '0';
+               entry->mode = mode;
+               entry->next = NULL;
 
                bufptr += len + 20;
                size -= len + 20;
 
-               if (S_ISDIR(mode)) {
-                       obj = &lookup_tree(file_sha1)->object;
+               if (entry->directory) {
+                       entry->item.tree = lookup_tree(file_sha1);
+                       obj = &entry->item.tree->object;
                } else {
-                       obj = &lookup_blob(file_sha1)->object;
+                       entry->item.blob = lookup_blob(file_sha1);
+                       obj = &entry->item.blob->object;
                }
-               add_ref(&item->object, obj);
+               if (obj)
+                       n_refs++;
+               *list_p = entry;
+               list_p = &entry->next;
+       }
+
+       if (track_object_refs) {
+               struct tree_entry_list *entry;
+               unsigned i = 0;
+               struct object_refs *refs = alloc_object_refs(n_refs);
+               for (entry = item->entries; entry; entry = entry->next)
+                       refs->ref[i++] = entry->item.any;
+               set_object_refs(&item->object, refs);
        }
+
        return 0;
 }
+
+int parse_tree(struct tree *item)
+{
+        char type[20];
+        void *buffer;
+        unsigned long size;
+        int ret;
+
+       if (item->object.parsed)
+               return 0;
+       buffer = 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)) {
+               free(buffer);
+               return error("Object %s not a tree",
+                            sha1_to_hex(item->object.sha1));
+       }
+       ret = parse_tree_buffer(item, buffer, size);
+       free(buffer);
+       return ret;
+}
+
+struct tree *parse_tree_indirect(const unsigned char *sha1)
+{
+       struct object *obj = parse_object(sha1);
+       do {
+               if (!obj)
+                       return NULL;
+               if (obj->type == tree_type)
+                       return (struct tree *) obj;
+               else if (obj->type == commit_type)
+                       obj = &(((struct commit *) obj)->tree->object);
+               else if (obj->type == tag_type)
+                       obj = ((struct tag *) obj)->tagged;
+               else
+                       return NULL;
+               if (!obj->parsed)
+                       parse_object(obj->sha1);
+       } while (1);
+}