Andrew's git - gitweb.git/blob

   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
   8static int fill_mmfile_blob(mmfile_t *f, struct blob *obj)
   9{
  10        void *buf;
  11        unsigned long size;
  12        enum object_type type;
  13
  14        buf = read_sha1_file(obj->object.sha1, &type, &size);
  15        if (!buf)
  16                return -1;
  17        if (type != OBJ_BLOB)
  18                return -1;
  19        f->ptr = buf;
  20        f->size = size;
  21        return 0;
  22}
  23
  24static void free_mmfile(mmfile_t *f)
  25{
  26        free(f->ptr);
  27}
  28
  29static void *three_way_filemerge(const char *path, mmfile_t *base, mmfile_t *our, mmfile_t *their, unsigned long *size)
  30{
  31        int merge_status;
  32        mmbuffer_t res;
  33
  34        /*
  35         * This function is only used by cmd_merge_tree, which
  36         * does not respect the merge.conflictstyle option.
  37         * There is no need to worry about a label for the
  38         * common ancestor.
  39         */
  40        merge_status = ll_merge(&res, path, base, NULL,
  41                                our, ".our", their, ".their", NULL);
  42        if (merge_status < 0)
  43                return NULL;
  44
  45        *size = res.size;
  46        return res.ptr;
  47}
  48
  49static int common_outf(void *priv_, mmbuffer_t *mb, int nbuf)
  50{
  51        int i;
  52        mmfile_t *dst = priv_;
  53
  54        for (i = 0; i < nbuf; i++) {
  55                memcpy(dst->ptr + dst->size, mb[i].ptr, mb[i].size);
  56                dst->size += mb[i].size;
  57        }
  58        return 0;
  59}
  60
  61static int generate_common_file(mmfile_t *res, mmfile_t *f1, mmfile_t *f2)
  62{
  63        unsigned long size = f1->size < f2->size ? f1->size : f2->size;
  64        void *ptr = xmalloc(size);
  65        xpparam_t xpp;
  66        xdemitconf_t xecfg;
  67        xdemitcb_t ecb;
  68
  69        memset(&xpp, 0, sizeof(xpp));
  70        xpp.flags = 0;
  71        memset(&xecfg, 0, sizeof(xecfg));
  72        xecfg.ctxlen = 3;
  73        xecfg.flags = XDL_EMIT_COMMON;
  74        ecb.outf = common_outf;
  75
  76        res->ptr = ptr;
  77        res->size = 0;
  78
  79        ecb.priv = res;
  80        return xdi_diff(f1, f2, &xpp, &xecfg, &ecb);
  81}
  82
  83void *merge_blobs(const char *path, struct blob *base, struct blob *our, struct blob *their, unsigned long *size)
  84{
  85        void *res = NULL;
  86        mmfile_t f1, f2, common;
  87
  88        /*
  89         * Removed in either branch?
  90         *
  91         * NOTE! This depends on the caller having done the
  92         * proper warning about removing a file that got
  93         * modified in the other branch!
  94         */
  95        if (!our || !their) {
  96                enum object_type type;
  97                if (base)
  98                        return NULL;
  99                if (!our)
 100                        our = their;
 101                return read_sha1_file(our->object.sha1, &type, size);
 102        }
 103
 104        if (fill_mmfile_blob(&f1, our) < 0)
 105                goto out_no_mmfile;
 106        if (fill_mmfile_blob(&f2, their) < 0)
 107                goto out_free_f1;
 108
 109        if (base) {
 110                if (fill_mmfile_blob(&common, base) < 0)
 111                        goto out_free_f2_f1;
 112        } else {
 113                if (generate_common_file(&common, &f1, &f2) < 0)
 114                        goto out_free_f2_f1;
 115        }
 116        res = three_way_filemerge(path, &common, &f1, &f2, size);
 117        free_mmfile(&common);
 118out_free_f2_f1:
 119        free_mmfile(&f2);
 120out_free_f1:
 121        free_mmfile(&f1);
 122out_no_mmfile:
 123        return res;
 124}