merge-blobs.c

   1 #include "git-compat-util.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 = repo_read_object_file(the_repository, &obj->object.oid, &type,
  16                                     &size);
  17         if (!buf)
  18                 return -1;
  19         if (type != OBJ_BLOB) {
  20                 free(buf);
  21                 return -1;
  22         }
  23         f->ptr = buf;
  24         f->size = size;
  25         return 0;
  26 }
  27
  28 static void free_mmfile(mmfile_t *f)
  29 {
  30         free(f->ptr);
  31 }
  32
  33 static void *three_way_filemerge(struct index_state *istate,
  34                                  const char *path,
  35                                  mmfile_t *base,
  36                                  mmfile_t *our,
  37                                  mmfile_t *their,
  38                                  unsigned long *size)
  39 {
  40         enum ll_merge_result merge_status;
  41         mmbuffer_t res;
  42
  43         /*
  44          * This function is only used by cmd_merge_tree, which
  45          * does not respect the merge.conflictstyle option.
  46          * There is no need to worry about a label for the
  47          * common ancestor.
  48          */
  49         merge_status = ll_merge(&res, path, base, NULL,
  50                                 our, ".our", their, ".their",
  51                                 istate, NULL);
  52         if (merge_status < 0)
  53                 return NULL;
  54         if (merge_status == LL_MERGE_BINARY_CONFLICT)
  55                 warning("Cannot merge binary files: %s (%s vs. %s)",
  56                         path, ".our", ".their");
  57
  58         *size = res.size;
  59         return res.ptr;
  60 }
  61
  62 void *merge_blobs(struct index_state *istate, const char *path,
  63                   struct blob *base, struct blob *our,
  64                   struct blob *their, unsigned long *size)
  65 {
  66         void *res = NULL;
  67         mmfile_t f1, f2, common;
  68
  69         /*
  70          * Removed in either branch?
  71          *
  72          * NOTE! This depends on the caller having done the
  73          * proper warning about removing a file that got
  74          * modified in the other branch!
  75          */
  76         if (!our || !their) {
  77                 enum object_type type;
  78                 if (base)
  79                         return NULL;
  80                 if (!our)
  81                         our = their;
  82                 return repo_read_object_file(the_repository, &our->object.oid,
  83                                              &type, size);
  84         }
  85
  86         if (fill_mmfile_blob(&f1, our) < 0)
  87                 goto out_no_mmfile;
  88         if (fill_mmfile_blob(&f2, their) < 0)
  89                 goto out_free_f1;
  90
  91         if (base) {
  92                 if (fill_mmfile_blob(&common, base) < 0)
  93                         goto out_free_f2_f1;
  94         } else {
  95                 common.ptr = xstrdup("");
  96                 common.size = 0;
  97         }
  98         res = three_way_filemerge(istate, path, &common, &f1, &f2, size);
  99         free_mmfile(&common);
 100 out_free_f2_f1:
 101         free_mmfile(&f2);
 102 out_free_f1:
 103         free_mmfile(&f1);
 104 out_no_mmfile:
 105         return res;
 106 }