ll-merge.c: remove implicit dependency on the_index
[git] / merge-blobs.c
1 #include "cache.h"
2 #include "run-command.h"
3 #include "xdiff-interface.h"
4 #include "ll-merge.h"
5 #include "blob.h"
6 #include "merge-blobs.h"
7 #include "object-store.h"
8
9 static int fill_mmfile_blob(mmfile_t *f, struct blob *obj)
10 {
11         void *buf;
12         unsigned long size;
13         enum object_type type;
14
15         buf = read_object_file(&obj->object.oid, &type, &size);
16         if (!buf)
17                 return -1;
18         if (type != OBJ_BLOB) {
19                 free(buf);
20                 return -1;
21         }
22         f->ptr = buf;
23         f->size = size;
24         return 0;
25 }
26
27 static void free_mmfile(mmfile_t *f)
28 {
29         free(f->ptr);
30 }
31
32 static void *three_way_filemerge(const char *path, mmfile_t *base, mmfile_t *our, mmfile_t *their, unsigned long *size)
33 {
34         int merge_status;
35         mmbuffer_t res;
36
37         /*
38          * This function is only used by cmd_merge_tree, which
39          * does not respect the merge.conflictstyle option.
40          * There is no need to worry about a label for the
41          * common ancestor.
42          */
43         merge_status = ll_merge(&res, path, base, NULL,
44                                 our, ".our", their, ".their",
45                                 &the_index, NULL);
46         if (merge_status < 0)
47                 return NULL;
48
49         *size = res.size;
50         return res.ptr;
51 }
52
53 void *merge_blobs(const char *path, struct blob *base, struct blob *our, struct blob *their, unsigned long *size)
54 {
55         void *res = NULL;
56         mmfile_t f1, f2, common;
57
58         /*
59          * Removed in either branch?
60          *
61          * NOTE! This depends on the caller having done the
62          * proper warning about removing a file that got
63          * modified in the other branch!
64          */
65         if (!our || !their) {
66                 enum object_type type;
67                 if (base)
68                         return NULL;
69                 if (!our)
70                         our = their;
71                 return read_object_file(&our->object.oid, &type, size);
72         }
73
74         if (fill_mmfile_blob(&f1, our) < 0)
75                 goto out_no_mmfile;
76         if (fill_mmfile_blob(&f2, their) < 0)
77                 goto out_free_f1;
78
79         if (base) {
80                 if (fill_mmfile_blob(&common, base) < 0)
81                         goto out_free_f2_f1;
82         } else {
83                 common.ptr = xstrdup("");
84                 common.size = 0;
85         }
86         res = three_way_filemerge(path, &common, &f1, &f2, size);
87         free_mmfile(&common);
88 out_free_f2_f1:
89         free_mmfile(&f2);
90 out_free_f1:
91         free_mmfile(&f1);
92 out_no_mmfile:
93         return res;
94 }