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
   7static int fill_mmfile_blob(mmfile_t *f, struct blob *obj)
   8{
   9        void *buf;
  10        unsigned long size;
  11        enum object_type type;
  12
  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;
  21}
  22
  23static void free_mmfile(mmfile_t *f)
  24{
  25        free(f->ptr);
  26}
  27
  28static void *three_way_filemerge(const char *path, mmfile_t *base, mmfile_t *our, mmfile_t *their, unsigned long *size)
  29{
  30        int merge_status;
  31        mmbuffer_t res;
  32
  33        merge_status = ll_merge(&res, path, base,
  34                                our, ".our", their, ".their", 0);
  35        if (merge_status < 0)
  36                return NULL;
  37
  38        *size = res.size;
  39        return res.ptr;
  40}
  41
  42static int common_outf(void *priv_, mmbuffer_t *mb, int nbuf)
  43{
  44        int i;
  45        mmfile_t *dst = priv_;
  46
  47        for (i = 0; i < nbuf; i++) {
  48                memcpy(dst->ptr + dst->size, mb[i].ptr, mb[i].size);
  49                dst->size += mb[i].size;
  50        }
  51        return 0;
  52}
  53
  54static int generate_common_file(mmfile_t *res, mmfile_t *f1, mmfile_t *f2)
  55{
  56        unsigned long size = f1->size < f2->size ? f1->size : f2->size;
  57        void *ptr = xmalloc(size);
  58        xpparam_t xpp;
  59        xdemitconf_t xecfg;
  60        xdemitcb_t ecb;
  61
  62        memset(&xpp, 0, sizeof(xpp));
  63        xpp.flags = XDF_NEED_MINIMAL;
  64        memset(&xecfg, 0, sizeof(xecfg));
  65        xecfg.ctxlen = 3;
  66        xecfg.flags = XDL_EMIT_COMMON;
  67        ecb.outf = common_outf;
  68
  69        res->ptr = ptr;
  70        res->size = 0;
  71
  72        ecb.priv = res;
  73        return xdi_diff(f1, f2, &xpp, &xecfg, &ecb);
  74}
  75
  76void *merge_file(const char *path, struct blob *base, struct blob *our, struct blob *their, unsigned long *size)
  77{
  78        void *res = NULL;
  79        mmfile_t f1, f2, common;
  80
  81        /*
  82         * Removed in either branch?
  83         *
  84         * NOTE! This depends on the caller having done the
  85         * proper warning about removing a file that got
  86         * modified in the other branch!
  87         */
  88        if (!our || !their) {
  89                enum object_type type;
  90                if (base)
  91                        return NULL;
  92                if (!our)
  93                        our = their;
  94                return read_sha1_file(our->object.sha1, &type, size);
  95        }
  96
  97        if (fill_mmfile_blob(&f1, our) < 0)
  98                goto out_no_mmfile;
  99        if (fill_mmfile_blob(&f2, their) < 0)
 100                goto out_free_f1;
 101
 102        if (base) {
 103                if (fill_mmfile_blob(&common, base) < 0)
 104                        goto out_free_f2_f1;
 105        } else {
 106                if (generate_common_file(&common, &f1, &f2) < 0)
 107                        goto out_free_f2_f1;
 108        }
 109        res = three_way_filemerge(path, &common, &f1, &f2, size);
 110        free_mmfile(&common);
 111out_free_f2_f1:
 112        free_mmfile(&f2);
 113out_free_f1:
 114        free_mmfile(&f1);
 115out_no_mmfile:
 116        return res;
 117}