git-tar-tree: no more void pointer arithmetic

[git.git] / tree-walk.c

diff --git a/tree-walk.c b/tree-walk.c
index 0735f40..297c697 100644 (file)
--- a/tree-walk.c
+++ b/tree-walk.c
@@ -1,5 +1,6 @@
 #include "cache.h"
 #include "tree-walk.h"
+#include "tree.h"
 
 void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1)
 {
@@ -7,7 +8,7 @@ void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1)
        void *buf = NULL;
 
        if (sha1) {
-               buf = read_object_with_reference(sha1, "tree", &size, NULL);
+               buf = read_object_with_reference(sha1, tree_type, &size, NULL);
                if (!buf)
                        die("unable to read tree %s", sha1_to_hex(sha1));
        }
@@ -36,7 +37,7 @@ static void entry_extract(struct tree_desc *t, struct name_entry *a)
 
 void update_tree_entry(struct tree_desc *desc)
 {
-       void *buf = desc->buf;
+       const void *buf = desc->buf;
        unsigned long size = desc->size;
        int len = strlen(buf) + 1 + 20;
 
@@ -46,22 +47,66 @@ void update_tree_entry(struct tree_desc *desc)
        desc->size = size - len;
 }
 
+static const char *get_mode(const char *str, unsigned int *modep)
+{
+       unsigned char c;
+       unsigned int mode = 0;
+
+       while ((c = *str++) != ' ') {
+               if (c < '0' || c > '7')
+                       return NULL;
+               mode = (mode << 3) + (c - '0');
+       }
+       *modep = mode;
+       return str;
+}
+
 const unsigned char *tree_entry_extract(struct tree_desc *desc, const char **pathp, unsigned int *modep)
 {
-       void *tree = desc->buf;
+       const void *tree = desc->buf;
        unsigned long size = desc->size;
        int len = strlen(tree)+1;
        const unsigned char *sha1 = tree + len;
-       const char *path = strchr(tree, ' ');
+       const char *path;
        unsigned int mode;
 
-       if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
+       path = get_mode(tree, &mode);
+       if (!path || size < len + 20)
                die("corrupt tree file");
-       *pathp = path+1;
+       *pathp = path;
        *modep = canon_mode(mode);
        return sha1;
 }
 
+int tree_entry(struct tree_desc *desc, struct name_entry *entry)
+{
+       const void *tree = desc->buf, *path;
+       unsigned long len, size = desc->size;
+
+       if (!size)
+               return 0;
+
+       path = get_mode(tree, &entry->mode);
+       if (!path)
+               die("corrupt tree file");
+
+       entry->path = path;
+       len = strlen(path);
+       entry->pathlen = len;
+
+       path += len + 1;
+       entry->sha1 = path;
+
+       path += 20;
+       len = path - tree;
+       if (len > size)
+               die("corrupt tree file");
+
+       desc->buf = path;
+       desc->size = size - len;
+       return 1;
+}
+
 void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callback_t callback)
 {
        struct name_entry *entry = xmalloc(n*sizeof(*entry));
@@ -114,3 +159,53 @@ void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callb
        free(entry);
 }
 
+static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char *result, unsigned *mode)
+{
+       int namelen = strlen(name);
+       while (t->size) {
+               const char *entry;
+               const unsigned char *sha1;
+               int entrylen, cmp;
+
+               sha1 = tree_entry_extract(t, &entry, mode);
+               update_tree_entry(t);
+               entrylen = strlen(entry);
+               if (entrylen > namelen)
+                       continue;
+               cmp = memcmp(name, entry, entrylen);
+               if (cmp > 0)
+                       continue;
+               if (cmp < 0)
+                       break;
+               if (entrylen == namelen) {
+                       memcpy(result, sha1, 20);
+                       return 0;
+               }
+               if (name[entrylen] != '/')
+                       continue;
+               if (!S_ISDIR(*mode))
+                       break;
+               if (++entrylen == namelen) {
+                       memcpy(result, sha1, 20);
+                       return 0;
+               }
+               return get_tree_entry(sha1, name + entrylen, result, mode);
+       }
+       return -1;
+}
+
+int get_tree_entry(const unsigned char *tree_sha1, const char *name, unsigned char *sha1, unsigned *mode)
+{
+       int retval;
+       void *tree;
+       struct tree_desc t;
+
+       tree = read_object_with_reference(tree_sha1, tree_type, &t.size, NULL);
+       if (!tree)
+               return -1;
+       t.buf = tree;
+       retval = find_tree_entry(&t, name, sha1, mode);
+       free(tree);
+       return retval;
+}
+