[PATCH] introduce xmalloc and xrealloc
[git.git] / tree.c
1 #include "tree.h"
2 #include "blob.h"
3 #include "cache.h"
4 #include <stdlib.h>
5
6 const char *tree_type = "tree";
7
8 static int read_one_entry(unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage)
9 {
10         int len = strlen(pathname);
11         unsigned int size = cache_entry_size(baselen + len);
12         struct cache_entry *ce = xmalloc(size);
13
14         memset(ce, 0, size);
15
16         ce->ce_mode = create_ce_mode(mode);
17         ce->ce_flags = create_ce_flags(baselen + len, stage);
18         memcpy(ce->name, base, baselen);
19         memcpy(ce->name + baselen, pathname, len+1);
20         memcpy(ce->sha1, sha1, 20);
21         return add_cache_entry(ce, 1);
22 }
23
24 static int read_tree_recursive(void *buffer, unsigned long size,
25                                const char *base, int baselen, int stage)
26 {
27         while (size) {
28                 int len = strlen(buffer)+1;
29                 unsigned char *sha1 = buffer + len;
30                 char *path = strchr(buffer, ' ')+1;
31                 unsigned int mode;
32
33                 if (size < len + 20 || sscanf(buffer, "%o", &mode) != 1)
34                         return -1;
35
36                 buffer = sha1 + 20;
37                 size -= len + 20;
38
39                 if (S_ISDIR(mode)) {
40                         int retval;
41                         int pathlen = strlen(path);
42                         char *newbase = xmalloc(baselen + 1 + pathlen);
43                         void *eltbuf;
44                         char elttype[20];
45                         unsigned long eltsize;
46
47                         eltbuf = read_sha1_file(sha1, elttype, &eltsize);
48                         if (!eltbuf || strcmp(elttype, "tree"))
49                                 return -1;
50                         memcpy(newbase, base, baselen);
51                         memcpy(newbase + baselen, path, pathlen);
52                         newbase[baselen + pathlen] = '/';
53                         retval = read_tree_recursive(eltbuf, eltsize,
54                                                      newbase,
55                                                      baselen + pathlen + 1, stage);
56                         free(eltbuf);
57                         free(newbase);
58                         if (retval)
59                                 return -1;
60                         continue;
61                 }
62                 if (read_one_entry(sha1, base, baselen, path, mode, stage) < 0)
63                         return -1;
64         }
65         return 0;
66 }
67
68 int read_tree(void *buffer, unsigned long size, int stage)
69 {
70         return read_tree_recursive(buffer, size, "", 0, stage);
71 }
72
73 struct tree *lookup_tree(unsigned char *sha1)
74 {
75         struct object *obj = lookup_object(sha1);
76         if (!obj) {
77                 struct tree *ret = xmalloc(sizeof(struct tree));
78                 memset(ret, 0, sizeof(struct tree));
79                 created_object(sha1, &ret->object);
80                 ret->object.type = tree_type;
81                 return ret;
82         }
83         if (obj->type != tree_type) {
84                 error("Object %s is a %s, not a tree", 
85                       sha1_to_hex(sha1), obj->type);
86                 return NULL;
87         }
88         return (struct tree *) obj;
89 }
90
91 int parse_tree(struct tree *item)
92 {
93         char type[20];
94         void *buffer, *bufptr;
95         unsigned long size;
96         struct tree_entry_list **list_p;
97         if (item->object.parsed)
98                 return 0;
99         item->object.parsed = 1;
100         buffer = bufptr = read_sha1_file(item->object.sha1, type, &size);
101         if (!buffer)
102                 return error("Could not read %s",
103                              sha1_to_hex(item->object.sha1));
104         if (strcmp(type, tree_type))
105                 return error("Object %s not a tree",
106                              sha1_to_hex(item->object.sha1));
107         list_p = &item->entries;
108         while (size) {
109                 struct object *obj;
110                 struct tree_entry_list *entry;
111                 int len = 1+strlen(bufptr);
112                 unsigned char *file_sha1 = bufptr + len;
113                 char *path = strchr(bufptr, ' ');
114                 unsigned int mode;
115                 if (size < len + 20 || !path || 
116                     sscanf(bufptr, "%o", &mode) != 1)
117                         return -1;
118
119                 entry = xmalloc(sizeof(struct tree_entry_list));
120                 entry->name = strdup(path + 1);
121                 entry->directory = S_ISDIR(mode);
122                 entry->executable = mode & S_IXUSR;
123                 entry->next = NULL;
124
125                 /* Warn about trees that don't do the recursive thing.. */
126                 if (strchr(path, '/')) {
127                         item->has_full_path = 1;
128                 }
129
130                 bufptr += len + 20;
131                 size -= len + 20;
132
133                 if (entry->directory) {
134                         entry->item.tree = lookup_tree(file_sha1);
135                         obj = &entry->item.tree->object;
136                 } else {
137                         entry->item.blob = lookup_blob(file_sha1);
138                         obj = &entry->item.blob->object;
139                 }
140                 if (obj)
141                         add_ref(&item->object, obj);
142
143                 *list_p = entry;
144                 list_p = &entry->next;
145         }
146         return 0;
147 }