src/merge_file.c

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7
   8 #include "common.h"
   9 #include "repository.h"
  10 #include "merge_file.h"
  11
  12 #include "git2/repository.h"
  13 #include "git2/object.h"
  14 #include "git2/index.h"
  15
  16 #include "xdiff/xdiff.h"
  17
  18 #define GIT_MERGE_FILE_SIDE_EXISTS(X)   ((X)->mode != 0)
  19
  20 GIT_INLINE(const char *) merge_file_best_path(
  21         const git_merge_file_input *ancestor,
  22         const git_merge_file_input *ours,
  23         const git_merge_file_input *theirs)
  24 {
  25         if (!GIT_MERGE_FILE_SIDE_EXISTS(ancestor)) {
  26                 if (strcmp(ours->path, theirs->path) == 0)
  27                         return ours->path;
  28
  29                 return NULL;
  30         }
  31
  32         if (strcmp(ancestor->path, ours->path) == 0)
  33                 return theirs->path;
  34         else if(strcmp(ancestor->path, theirs->path) == 0)
  35                 return ours->path;
  36
  37         return NULL;
  38 }
  39
  40 GIT_INLINE(int) merge_file_best_mode(
  41         const git_merge_file_input *ancestor,
  42         const git_merge_file_input *ours,
  43         const git_merge_file_input *theirs)
  44 {
  45         /*
  46          * If ancestor didn't exist and either ours or theirs is executable,
  47          * assume executable.  Otherwise, if any mode changed from the ancestor,
  48          * use that one.
  49          */
  50         if (!GIT_MERGE_FILE_SIDE_EXISTS(ancestor)) {
  51                 if (ours->mode == GIT_FILEMODE_BLOB_EXECUTABLE ||
  52                         theirs->mode == GIT_FILEMODE_BLOB_EXECUTABLE)
  53                         return GIT_FILEMODE_BLOB_EXECUTABLE;
  54
  55                 return GIT_FILEMODE_BLOB;
  56         }
  57
  58         if (ancestor->mode == ours->mode)
  59                 return theirs->mode;
  60         else if(ancestor->mode == theirs->mode)
  61                 return ours->mode;
  62
  63         return 0;
  64 }
  65
  66 int git_merge_file_input_from_index_entry(
  67         git_merge_file_input *input,
  68         git_repository *repo,
  69         const git_index_entry *entry)
  70 {
  71         git_odb *odb = NULL;
  72         int error = 0;
  73
  74         assert(input && repo && entry);
  75
  76         if (entry->mode == 0)
  77                 return 0;
  78
  79         if ((error = git_repository_odb(&odb, repo)) < 0 ||
  80                 (error = git_odb_read(&input->odb_object, odb, &entry->oid)) < 0)
  81                 goto done;
  82
  83         input->mode = entry->mode;
  84         input->path = git__strdup(entry->path);
  85         input->mmfile.size = git_odb_object_size(input->odb_object);
  86         input->mmfile.ptr = (char *)git_odb_object_data(input->odb_object);
  87
  88         if (input->label == NULL)
  89                 input->label = entry->path;
  90
  91 done:
  92         git_odb_free(odb);
  93
  94         return error;
  95 }
  96
  97 int git_merge_file_input_from_diff_file(
  98         git_merge_file_input *input,
  99         git_repository *repo,
 100         const git_diff_file *file)
 101 {
 102         git_odb *odb = NULL;
 103         int error = 0;
 104
 105         assert(input && repo && file);
 106
 107         if (file->mode == 0)
 108                 return 0;
 109
 110         if ((error = git_repository_odb(&odb, repo)) < 0 ||
 111                 (error = git_odb_read(&input->odb_object, odb, &file->oid)) < 0)
 112                 goto done;
 113
 114         input->mode = file->mode;
 115         input->path = git__strdup(file->path);
 116         input->mmfile.size = git_odb_object_size(input->odb_object);
 117         input->mmfile.ptr = (char *)git_odb_object_data(input->odb_object);
 118
 119         if (input->label == NULL)
 120                 input->label = file->path;
 121
 122 done:
 123         git_odb_free(odb);
 124
 125         return error;
 126 }
 127
 128 int git_merge_files(
 129         git_merge_file_result *out,
 130         git_merge_file_input *ancestor,
 131         git_merge_file_input *ours,
 132         git_merge_file_input *theirs,
 133         git_merge_automerge_flags flags)
 134 {
 135         xmparam_t xmparam;
 136         mmbuffer_t mmbuffer;
 137         int xdl_result;
 138         int error = 0;
 139
 140         assert(out && ancestor && ours && theirs);
 141
 142         memset(out, 0x0, sizeof(git_merge_file_result));
 143
 144         if (!GIT_MERGE_FILE_SIDE_EXISTS(ours) || !GIT_MERGE_FILE_SIDE_EXISTS(theirs))
 145                 return 0;
 146
 147         memset(&xmparam, 0x0, sizeof(xmparam_t));
 148         xmparam.ancestor = ancestor->label;
 149         xmparam.file1 = ours->label;
 150         xmparam.file2 = theirs->label;
 151
 152         out->path = merge_file_best_path(ancestor, ours, theirs);
 153         out->mode = merge_file_best_mode(ancestor, ours, theirs);
 154
 155         if (flags == GIT_MERGE_AUTOMERGE_FAVOR_OURS)
 156                 xmparam.favor = XDL_MERGE_FAVOR_OURS;
 157
 158         if (flags == GIT_MERGE_AUTOMERGE_FAVOR_THEIRS)
 159                 xmparam.favor = XDL_MERGE_FAVOR_THEIRS;
 160
 161         if ((xdl_result = xdl_merge(&ancestor->mmfile, &ours->mmfile,
 162                 &theirs->mmfile, &xmparam, &mmbuffer)) < 0) {
 163                 giterr_set(GITERR_MERGE, "Failed to merge files.");
 164                 error = -1;
 165                 goto done;
 166         }
 167
 168         out->automergeable = (xdl_result == 0);
 169         out->data = (unsigned char *)mmbuffer.ptr;
 170         out->len = mmbuffer.size;
 171
 172 done:
 173         return error;
 174 }