gitweb: Add git_merge sub
[git/gsoc2010-gitweb.git] / merge-file.c
blobdb4d0d50d32d8852d1cb5173125e4173c3badb49
1 #include "cache.h"
2 #include "run-command.h"
3 #include "xdiff-interface.h"
4 #include "ll-merge.h"
5 #include "blob.h"
7 static int fill_mmfile_blob(mmfile_t *f, struct blob *obj)
9 void *buf;
10 unsigned long size;
11 enum object_type type;
13 buf = read_sha1_file(obj->object.sha1, &type, &size);
14 if (!buf)
15 return -1;
16 if (type != OBJ_BLOB)
17 return -1;
18 f->ptr = buf;
19 f->size = size;
20 return 0;
23 static void free_mmfile(mmfile_t *f)
25 free(f->ptr);
28 static void *three_way_filemerge(const char *path, mmfile_t *base, mmfile_t *our, mmfile_t *their, unsigned long *size)
30 int merge_status;
31 mmbuffer_t res;
34 * This function is only used by cmd_merge_tree, which
35 * does not respect the merge.conflictstyle option.
36 * There is no need to worry about a label for the
37 * common ancestor.
39 merge_status = ll_merge(&res, path, base, NULL,
40 our, ".our", their, ".their", 0);
41 if (merge_status < 0)
42 return NULL;
44 *size = res.size;
45 return res.ptr;
48 static int common_outf(void *priv_, mmbuffer_t *mb, int nbuf)
50 int i;
51 mmfile_t *dst = priv_;
53 for (i = 0; i < nbuf; i++) {
54 memcpy(dst->ptr + dst->size, mb[i].ptr, mb[i].size);
55 dst->size += mb[i].size;
57 return 0;
60 static int generate_common_file(mmfile_t *res, mmfile_t *f1, mmfile_t *f2)
62 unsigned long size = f1->size < f2->size ? f1->size : f2->size;
63 void *ptr = xmalloc(size);
64 xpparam_t xpp;
65 xdemitconf_t xecfg;
66 xdemitcb_t ecb;
68 memset(&xpp, 0, sizeof(xpp));
69 xpp.flags = 0;
70 memset(&xecfg, 0, sizeof(xecfg));
71 xecfg.ctxlen = 3;
72 xecfg.flags = XDL_EMIT_COMMON;
73 ecb.outf = common_outf;
75 res->ptr = ptr;
76 res->size = 0;
78 ecb.priv = res;
79 return xdi_diff(f1, f2, &xpp, &xecfg, &ecb);
82 void *merge_file(const char *path, struct blob *base, struct blob *our, struct blob *their, unsigned long *size)
84 void *res = NULL;
85 mmfile_t f1, f2, common;
88 * Removed in either branch?
90 * NOTE! This depends on the caller having done the
91 * proper warning about removing a file that got
92 * modified in the other branch!
94 if (!our || !their) {
95 enum object_type type;
96 if (base)
97 return NULL;
98 if (!our)
99 our = their;
100 return read_sha1_file(our->object.sha1, &type, size);
103 if (fill_mmfile_blob(&f1, our) < 0)
104 goto out_no_mmfile;
105 if (fill_mmfile_blob(&f2, their) < 0)
106 goto out_free_f1;
108 if (base) {
109 if (fill_mmfile_blob(&common, base) < 0)
110 goto out_free_f2_f1;
111 } else {
112 if (generate_common_file(&common, &f1, &f2) < 0)
113 goto out_free_f2_f1;
115 res = three_way_filemerge(path, &common, &f1, &f2, size);
116 free_mmfile(&common);
117 out_free_f2_f1:
118 free_mmfile(&f2);
119 out_free_f1:
120 free_mmfile(&f1);
121 out_no_mmfile:
122 return res;