Code

Merge branch 'jc/maint-1.6.0-split-diff-metainfo' into jc/maint-split-diff-metainfo
authorJunio C Hamano <gitster@pobox.com>
Tue, 27 Jan 2009 09:08:02 +0000 (01:08 -0800)
committerJunio C Hamano <gitster@pobox.com>
Tue, 27 Jan 2009 09:08:02 +0000 (01:08 -0800)
This is an evil merge, as a test added since 1.6.0 expects an incorrect
behaviour the merged commit fixes.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
1  2 
diff.c
t/t4030-diff-textconv.sh

diff --combined diff.c
index 5b85b4077a1d3e333d6af86127bf9473b295c837,6fea3c03476ac1817453a61fad0cda93a954df9a..416c5aa722afc8d10e4bc910e7b297b3eb0a2760
--- 1/diff.c
--- 2/diff.c
+++ b/diff.c
@@@ -11,7 -11,6 +11,7 @@@
  #include "attr.h"
  #include "run-command.h"
  #include "utf8.h"
 +#include "userdiff.h"
  
  #ifdef NO_FAST_WORKING_DIRECTORY
  #define FAST_WORKING_DIRECTORY 0
  
  static int diff_detect_rename_default;
  static int diff_rename_limit_default = 200;
 +static int diff_suppress_blank_empty;
  int diff_use_color_default = -1;
  static const char *external_diff_cmd_cfg;
  int diff_auto_refresh_index = 1;
 +static int diff_mnemonic_prefix;
  
  static char diff_colors[][COLOR_MAXLEN] = {
        "\033[m",       /* reset */
@@@ -38,9 -35,6 +38,9 @@@
        "\033[41m",     /* WHITESPACE (red background) */
  };
  
 +static void diff_filespec_load_driver(struct diff_filespec *one);
 +static char *run_textconv(const char *, struct diff_filespec *, size_t *);
 +
  static int parse_diff_color_slot(const char *var, int ofs)
  {
        if (!strcasecmp(var+ofs, "plain"))
        die("bad config variable '%s'", var);
  }
  
 -static struct ll_diff_driver {
 -      const char *name;
 -      struct ll_diff_driver *next;
 -      const char *cmd;
 -} *user_diff, **user_diff_tail;
 -
 -/*
 - * Currently there is only "diff.<drivername>.command" variable;
 - * because there are "diff.color.<slot>" variables, we are parsing
 - * this in a bit convoluted way to allow low level diff driver
 - * called "color".
 - */
 -static int parse_lldiff_command(const char *var, const char *ep, const char *value)
 -{
 -      const char *name;
 -      int namelen;
 -      struct ll_diff_driver *drv;
 -
 -      name = var + 5;
 -      namelen = ep - name;
 -      for (drv = user_diff; drv; drv = drv->next)
 -              if (!strncmp(drv->name, name, namelen) && !drv->name[namelen])
 -                      break;
 -      if (!drv) {
 -              drv = xcalloc(1, sizeof(struct ll_diff_driver));
 -              drv->name = xmemdupz(name, namelen);
 -              if (!user_diff_tail)
 -                      user_diff_tail = &user_diff;
 -              *user_diff_tail = drv;
 -              user_diff_tail = &(drv->next);
 -      }
 -
 -      return git_config_string(&(drv->cmd), var, value);
 -}
 -
 -/*
 - * 'diff.<what>.funcname' attribute can be specified in the configuration
 - * to define a customized regexp to find the beginning of a function to
 - * be used for hunk header lines of "diff -p" style output.
 - */
 -struct funcname_pattern_entry {
 -      char *name;
 -      char *pattern;
 -      int cflags;
 -};
 -static struct funcname_pattern_list {
 -      struct funcname_pattern_list *next;
 -      struct funcname_pattern_entry e;
 -} *funcname_pattern_list;
 -
 -static int parse_funcname_pattern(const char *var, const char *ep, const char *value, int cflags)
 -{
 -      const char *name;
 -      int namelen;
 -      struct funcname_pattern_list *pp;
 -
 -      name = var + 5; /* "diff." */
 -      namelen = ep - name;
 -
 -      for (pp = funcname_pattern_list; pp; pp = pp->next)
 -              if (!strncmp(pp->e.name, name, namelen) && !pp->e.name[namelen])
 -                      break;
 -      if (!pp) {
 -              pp = xcalloc(1, sizeof(*pp));
 -              pp->e.name = xmemdupz(name, namelen);
 -              pp->next = funcname_pattern_list;
 -              funcname_pattern_list = pp;
 -      }
 -      free(pp->e.pattern);
 -      pp->e.pattern = xstrdup(value);
 -      pp->e.cflags = cflags;
 -      return 0;
 -}
 -
  /*
   * These are to give UI layer defaults.
   * The core-level commands such as git-diff-files should
@@@ -86,12 -154,14 +86,12 @@@ int git_diff_ui_config(const char *var
                diff_auto_refresh_index = git_config_bool(var, value);
                return 0;
        }
 +      if (!strcmp(var, "diff.mnemonicprefix")) {
 +              diff_mnemonic_prefix = git_config_bool(var, value);
 +              return 0;
 +      }
        if (!strcmp(var, "diff.external"))
                return git_config_string(&external_diff_cmd_cfg, var, value);
 -      if (!prefixcmp(var, "diff.")) {
 -              const char *ep = strrchr(var, '.');
 -
 -              if (ep != var + 4 && !strcmp(ep, ".command"))
 -                      return parse_lldiff_command(var, ep, value);
 -      }
  
        return git_diff_basic_config(var, value, cb);
  }
@@@ -103,12 -173,6 +103,12 @@@ int git_diff_basic_config(const char *v
                return 0;
        }
  
 +      switch (userdiff_config(var, value)) {
 +              case 0: break;
 +              case -1: return -1;
 +              default: return 0;
 +      }
 +
        if (!prefixcmp(var, "diff.color.") || !prefixcmp(var, "color.diff.")) {
                int slot = parse_diff_color_slot(var, 11);
                if (!value)
                return 0;
        }
  
 -      if (!prefixcmp(var, "diff.")) {
 -              const char *ep = strrchr(var, '.');
 -              if (ep != var + 4) {
 -                      if (!strcmp(ep, ".funcname")) {
 -                              if (!value)
 -                                      return config_error_nonbool(var);
 -                              return parse_funcname_pattern(var, ep, value,
 -                                      0);
 -                      } else if (!strcmp(ep, ".xfuncname")) {
 -                              if (!value)
 -                                      return config_error_nonbool(var);
 -                              return parse_funcname_pattern(var, ep, value,
 -                                      REG_EXTENDED);
 -                      }
 -              }
 +      /* like GNU diff's --suppress-blank-empty option  */
 +      if (!strcmp(var, "diff.suppressblankempty") ||
 +                      /* for backwards compatibility */
 +                      !strcmp(var, "diff.suppress-blank-empty")) {
 +              diff_suppress_blank_empty = git_config_bool(var, value);
 +              return 0;
        }
  
        return git_color_default_config(var, value, cb);
@@@ -132,8 -205,9 +132,8 @@@ static char *quote_two(const char *one
  {
        int need_one = quote_c_style(one, NULL, NULL, 1);
        int need_two = quote_c_style(two, NULL, NULL, 1);
 -      struct strbuf res;
 +      struct strbuf res = STRBUF_INIT;
  
 -      strbuf_init(&res, 0);
        if (need_one + need_two) {
                strbuf_addch(&res, '"');
                quote_c_style(one, &res, NULL, 1);
@@@ -231,8 -305,6 +231,8 @@@ static void emit_rewrite_diff(const cha
                              const char *name_b,
                              struct diff_filespec *one,
                              struct diff_filespec *two,
 +                            const char *textconv_one,
 +                            const char *textconv_two,
                              struct diff_options *o)
  {
        int lc_a, lc_b;
        const char *new = diff_get_color(color_diff, DIFF_FILE_NEW);
        const char *reset = diff_get_color(color_diff, DIFF_RESET);
        static struct strbuf a_name = STRBUF_INIT, b_name = STRBUF_INIT;
 +      const char *a_prefix, *b_prefix;
 +      const char *data_one, *data_two;
 +      size_t size_one, size_two;
 +
 +      if (diff_mnemonic_prefix && DIFF_OPT_TST(o, REVERSE_DIFF)) {
 +              a_prefix = o->b_prefix;
 +              b_prefix = o->a_prefix;
 +      } else {
 +              a_prefix = o->a_prefix;
 +              b_prefix = o->b_prefix;
 +      }
  
        name_a += (*name_a == '/');
        name_b += (*name_b == '/');
  
        strbuf_reset(&a_name);
        strbuf_reset(&b_name);
 -      quote_two_c_style(&a_name, o->a_prefix, name_a, 0);
 -      quote_two_c_style(&b_name, o->b_prefix, name_b, 0);
 +      quote_two_c_style(&a_name, a_prefix, name_a, 0);
 +      quote_two_c_style(&b_name, b_prefix, name_b, 0);
  
        diff_populate_filespec(one, 0);
        diff_populate_filespec(two, 0);
 -      lc_a = count_lines(one->data, one->size);
 -      lc_b = count_lines(two->data, two->size);
 +      if (textconv_one) {
 +              data_one = run_textconv(textconv_one, one, &size_one);
 +              if (!data_one)
 +                      die("unable to read files to diff");
 +      }
 +      else {
 +              data_one = one->data;
 +              size_one = one->size;
 +      }
 +      if (textconv_two) {
 +              data_two = run_textconv(textconv_two, two, &size_two);
 +              if (!data_two)
 +                      die("unable to read files to diff");
 +      }
 +      else {
 +              data_two = two->data;
 +              size_two = two->size;
 +      }
 +
 +      lc_a = count_lines(data_one, size_one);
 +      lc_b = count_lines(data_two, size_two);
        fprintf(o->file,
                "%s--- %s%s%s\n%s+++ %s%s%s\n%s@@ -",
                metainfo, a_name.buf, name_a_tab, reset,
        print_line_count(o->file, lc_b);
        fprintf(o->file, " @@%s\n", reset);
        if (lc_a)
 -              copy_file_with_prefix(o->file, '-', one->data, one->size, old, reset);
 +              copy_file_with_prefix(o->file, '-', data_one, size_one, old, reset);
        if (lc_b)
 -              copy_file_with_prefix(o->file, '+', two->data, two->size, new, reset);
 +              copy_file_with_prefix(o->file, '+', data_two, size_two, new, reset);
  }
  
  static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
        }
        else if (diff_populate_filespec(one, 0))
                return -1;
 +
        mf->ptr = one->data;
        mf->size = one->size;
        return 0;
@@@ -339,6 -380,7 +339,6 @@@ static void diff_words_append(char *lin
  }
  
  struct diff_words_data {
 -      struct xdiff_emit_state xm;
        struct diff_words_buffer minus, plus;
        FILE *file;
  };
@@@ -409,7 -451,6 +409,7 @@@ static void diff_words_show(struct diff
        mmfile_t minus, plus;
        int i;
  
 +      memset(&xpp, 0, sizeof(xpp));
        memset(&xecfg, 0, sizeof(xecfg));
        minus.size = diff_words->minus.text.size;
        minus.ptr = xmalloc(minus.size);
  
        xpp.flags = XDF_NEED_MINIMAL;
        xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
 -      ecb.outf = xdiff_outf;
 -      ecb.priv = diff_words;
 -      diff_words->xm.consume = fn_out_diff_words_aux;
 -      xdi_diff(&minus, &plus, &xpp, &xecfg, &ecb);
 -
 +      xdi_diff_outf(&minus, &plus, fn_out_diff_words_aux, diff_words,
 +                    &xpp, &xecfg, &ecb);
        free(minus.ptr);
        free(plus.ptr);
        diff_words->minus.text.size = diff_words->plus.text.size = 0;
  typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
  
  struct emit_callback {
 -      struct xdiff_emit_state xm;
        int nparents, color_diff;
        unsigned ws_rule;
        sane_truncate_fn truncate;
@@@ -553,12 -598,6 +553,12 @@@ static void fn_out_consume(void *priv, 
                ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
        }
  
 +      if (diff_suppress_blank_empty
 +          && len == 2 && line[0] == ' ' && line[1] == '\n') {
 +              line[0] = '\n';
 +              len = 1;
 +      }
 +
        /* This is not really necessary for now because
         * this codepath only deals with two-way diffs.
         */
@@@ -622,7 -661,7 +622,7 @@@ static char *pprint_rename(const char *
  {
        const char *old = a;
        const char *new = b;
 -      struct strbuf name;
 +      struct strbuf name = STRBUF_INIT;
        int pfx_length, sfx_length;
        int len_a = strlen(a);
        int len_b = strlen(b);
        int qlen_a = quote_c_style(a, NULL, NULL, 0);
        int qlen_b = quote_c_style(b, NULL, NULL, 0);
  
 -      strbuf_init(&name, 0);
        if (qlen_a || qlen_b) {
                quote_c_style(a, &name, NULL, 0);
                strbuf_addstr(&name, " => ");
  }
  
  struct diffstat_t {
 -      struct xdiff_emit_state xm;
 -
        int nr;
        int alloc;
        struct diffstat_file {
@@@ -772,7 -814,8 +772,7 @@@ static void fill_print_name(struct diff
                return;
  
        if (!file->is_renamed) {
 -              struct strbuf buf;
 -              strbuf_init(&buf, 0);
 +              struct strbuf buf = STRBUF_INIT;
                if (quote_c_style(file->name, &buf, NULL, 0)) {
                        pname = strbuf_detach(&buf, NULL);
                } else {
@@@ -1079,13 -1122,9 +1079,13 @@@ static void show_dirstat(struct diff_op
                /*
                 * Original minus copied is the removed material,
                 * added is the new material.  They are both damages
 -               * made to the preimage.
 +               * made to the preimage. In --dirstat-by-file mode, count
 +               * damaged files, not damaged lines. This is done by
 +               * counting only a single damaged line per file.
                 */
                damage = (p->one->size - copied) + added;
 +              if (DIFF_OPT_TST(options, DIRSTAT_BY_FILE) && damage > 0)
 +                      damage = 1;
  
                ALLOC_GROW(dir.files, dir.nr + 1, dir.alloc);
                dir.files[dir.nr].name = name;
@@@ -1118,6 -1157,7 +1118,6 @@@ static void free_diffstat_info(struct d
  }
  
  struct checkdiff_t {
 -      struct xdiff_emit_state xm;
        const char *filename;
        int lineno;
        struct diff_options *o;
@@@ -1292,55 -1332,123 +1292,55 @@@ static void emit_binary_diff(FILE *file
        emit_binary_diff_body(file, two, one);
  }
  
 -static void setup_diff_attr_check(struct git_attr_check *check)
 +static void diff_filespec_load_driver(struct diff_filespec *one)
  {
 -      static struct git_attr *attr_diff;
 -
 -      if (!attr_diff) {
 -              attr_diff = git_attr("diff", 4);
 -      }
 -      check[0].attr = attr_diff;
 +      if (!one->driver)
 +              one->driver = userdiff_find_by_path(one->path);
 +      if (!one->driver)
 +              one->driver = userdiff_find_by_name("default");
  }
  
 -static void diff_filespec_check_attr(struct diff_filespec *one)
 +int diff_filespec_is_binary(struct diff_filespec *one)
  {
 -      struct git_attr_check attr_diff_check;
 -      int check_from_data = 0;
 -
 -      if (one->checked_attr)
 -              return;
 -
 -      setup_diff_attr_check(&attr_diff_check);
 -      one->is_binary = 0;
 -      one->funcname_pattern_ident = NULL;
 -
 -      if (!git_checkattr(one->path, 1, &attr_diff_check)) {
 -              const char *value;
 -
 -              /* binaryness */
 -              value = attr_diff_check.value;
 -              if (ATTR_TRUE(value))
 -                      ;
 -              else if (ATTR_FALSE(value))
 -                      one->is_binary = 1;
 -              else
 -                      check_from_data = 1;
 -
 -              /* funcname pattern ident */
 -              if (ATTR_TRUE(value) || ATTR_FALSE(value) || ATTR_UNSET(value))
 -                      ;
 -              else
 -                      one->funcname_pattern_ident = value;
 -      }
 -
 -      if (check_from_data) {
 -              if (!one->data && DIFF_FILE_VALID(one))
 -                      diff_populate_filespec(one, 0);
 -
 -              if (one->data)
 -                      one->is_binary = buffer_is_binary(one->data, one->size);
 +      if (one->is_binary == -1) {
 +              diff_filespec_load_driver(one);
 +              if (one->driver->binary != -1)
 +                      one->is_binary = one->driver->binary;
 +              else {
 +                      if (!one->data && DIFF_FILE_VALID(one))
 +                              diff_populate_filespec(one, 0);
 +                      if (one->data)
 +                              one->is_binary = buffer_is_binary(one->data,
 +                                              one->size);
 +                      if (one->is_binary == -1)
 +                              one->is_binary = 0;
 +              }
        }
 +      return one->is_binary;
  }
  
 -int diff_filespec_is_binary(struct diff_filespec *one)
 +static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
  {
 -      diff_filespec_check_attr(one);
 -      return one->is_binary;
 +      diff_filespec_load_driver(one);
 +      return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
  }
  
 -static const struct funcname_pattern_entry *funcname_pattern(const char *ident)
 -{
 -      struct funcname_pattern_list *pp;
 -
 -      for (pp = funcname_pattern_list; pp; pp = pp->next)
 -              if (!strcmp(ident, pp->e.name))
 -                      return &pp->e;
 -      return NULL;
 -}
 -
 -static const struct funcname_pattern_entry builtin_funcname_pattern[] = {
 -      { "java",
 -        "!^[ \t]*(catch|do|for|if|instanceof|new|return|switch|throw|while)\n"
 -        "^[ \t]*(([ \t]*[A-Za-z_][A-Za-z_0-9]*){2,}[ \t]*\\([^;]*)$",
 -        REG_EXTENDED },
 -      { "pascal",
 -        "^((procedure|function|constructor|destructor|interface|"
 -              "implementation|initialization|finalization)[ \t]*.*)$"
 -        "|"
 -        "^(.*=[ \t]*(class|record).*)$",
 -        REG_EXTENDED },
 -      { "bibtex", "(@[a-zA-Z]{1,}[ \t]*\\{{0,1}[ \t]*[^ \t\"@',\\#}{~%]*).*$",
 -        REG_EXTENDED },
 -      { "tex",
 -        "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$",
 -        REG_EXTENDED },
 -      { "ruby", "^[ \t]*((class|module|def)[ \t].*)$",
 -        REG_EXTENDED },
 -};
 -
 -static const struct funcname_pattern_entry *diff_funcname_pattern(struct diff_filespec *one)
 +void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
  {
 -      const char *ident;
 -      const struct funcname_pattern_entry *pe;
 -      int i;
 -
 -      diff_filespec_check_attr(one);
 -      ident = one->funcname_pattern_ident;
 -
 -      if (!ident)
 -              /*
 -               * If the config file has "funcname.default" defined, that
 -               * regexp is used; otherwise NULL is returned and xemit uses
 -               * the built-in default.
 -               */
 -              return funcname_pattern("default");
 -
 -      /* Look up custom "funcname.$ident" regexp from config. */
 -      pe = funcname_pattern(ident);
 -      if (pe)
 -              return pe;
 -
 -      /*
 -       * And define built-in fallback patterns here.  Note that
 -       * these can be overridden by the user's config settings.
 -       */
 -      for (i = 0; i < ARRAY_SIZE(builtin_funcname_pattern); i++)
 -              if (!strcmp(ident, builtin_funcname_pattern[i].name))
 -                      return &builtin_funcname_pattern[i];
 +      if (!options->a_prefix)
 +              options->a_prefix = a;
 +      if (!options->b_prefix)
 +              options->b_prefix = b;
 +}
  
 -      return NULL;
 +static const char *get_textconv(struct diff_filespec *one)
 +{
 +      if (!DIFF_FILE_VALID(one))
 +              return NULL;
 +      if (!S_ISREG(one->mode))
 +              return NULL;
 +      diff_filespec_load_driver(one);
 +      return one->driver->textconv;
  }
  
  static void builtin_diff(const char *name_a,
        char *a_one, *b_two;
        const char *set = diff_get_color_opt(o, DIFF_METAINFO);
        const char *reset = diff_get_color_opt(o, DIFF_RESET);
 +      const char *a_prefix, *b_prefix;
 +      const char *textconv_one = NULL, *textconv_two = NULL;
 +
 +      if (DIFF_OPT_TST(o, ALLOW_TEXTCONV)) {
 +              textconv_one = get_textconv(one);
 +              textconv_two = get_textconv(two);
 +      }
 +
 +      diff_set_mnemonic_prefix(o, "a/", "b/");
 +      if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 +              a_prefix = o->b_prefix;
 +              b_prefix = o->a_prefix;
 +      } else {
 +              a_prefix = o->a_prefix;
 +              b_prefix = o->b_prefix;
 +      }
  
        /* Never use a non-valid filename anywhere if at all possible */
        name_a = DIFF_FILE_VALID(one) ? name_a : name_b;
        name_b = DIFF_FILE_VALID(two) ? name_b : name_a;
  
 -      a_one = quote_two(o->a_prefix, name_a + (*name_a == '/'));
 -      b_two = quote_two(o->b_prefix, name_b + (*name_b == '/'));
 +      a_one = quote_two(a_prefix, name_a + (*name_a == '/'));
 +      b_two = quote_two(b_prefix, name_b + (*name_b == '/'));
        lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
        lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
        fprintf(o->file, "%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
                 */
                if ((one->mode ^ two->mode) & S_IFMT)
                        goto free_ab_and_return;
 -              if (complete_rewrite) {
 -                      emit_rewrite_diff(name_a, name_b, one, two, o);
 +              if (complete_rewrite &&
 +                  (textconv_one || !diff_filespec_is_binary(one)) &&
 +                  (textconv_two || !diff_filespec_is_binary(two))) {
 +                      emit_rewrite_diff(name_a, name_b, one, two,
 +                                              textconv_one, textconv_two, o);
                        o->found_changes = 1;
                        goto free_ab_and_return;
                }
                die("unable to read files to diff");
  
        if (!DIFF_OPT_TST(o, TEXT) &&
 -          (diff_filespec_is_binary(one) || diff_filespec_is_binary(two))) {
 +          ( (diff_filespec_is_binary(one) && !textconv_one) ||
 +            (diff_filespec_is_binary(two) && !textconv_two) )) {
                /* Quite common confusing case */
                if (mf1.size == mf2.size &&
                    !memcmp(mf1.ptr, mf2.ptr, mf1.size))
                xdemitconf_t xecfg;
                xdemitcb_t ecb;
                struct emit_callback ecbdata;
 -              const struct funcname_pattern_entry *pe;
 +              const struct userdiff_funcname *pe;
 +
 +              if (textconv_one) {
 +                      size_t size;
 +                      mf1.ptr = run_textconv(textconv_one, one, &size);
 +                      if (!mf1.ptr)
 +                              die("unable to read files to diff");
 +                      mf1.size = size;
 +              }
 +              if (textconv_two) {
 +                      size_t size;
 +                      mf2.ptr = run_textconv(textconv_two, two, &size);
 +                      if (!mf2.ptr)
 +                              die("unable to read files to diff");
 +                      mf2.size = size;
 +              }
  
                pe = diff_funcname_pattern(one);
                if (!pe)
                        pe = diff_funcname_pattern(two);
  
 +              memset(&xpp, 0, sizeof(xpp));
                memset(&xecfg, 0, sizeof(xecfg));
                memset(&ecbdata, 0, sizeof(ecbdata));
                ecbdata.label_path = lbl;
                        xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
                else if (!prefixcmp(diffopts, "-u"))
                        xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
 -              ecb.outf = xdiff_outf;
 -              ecb.priv = &ecbdata;
 -              ecbdata.xm.consume = fn_out_consume;
                if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS)) {
                        ecbdata.diff_words =
                                xcalloc(1, sizeof(struct diff_words_data));
                        ecbdata.diff_words->file = o->file;
                }
 -              xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 +              xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
 +                            &xpp, &xecfg, &ecb);
                if (DIFF_OPT_TST(o, COLOR_DIFF_WORDS))
                        free_diff_words_data(&ecbdata);
 +              if (textconv_one)
 +                      free(mf1.ptr);
 +              if (textconv_two)
 +                      free(mf2.ptr);
        }
  
   free_ab_and_return:
@@@ -1539,11 -1609,11 +1539,11 @@@ static void builtin_diffstat(const cha
                xdemitconf_t xecfg;
                xdemitcb_t ecb;
  
 +              memset(&xpp, 0, sizeof(xpp));
                memset(&xecfg, 0, sizeof(xecfg));
                xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
 -              ecb.outf = xdiff_outf;
 -              ecb.priv = diffstat;
 -              xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 +              xdi_diff_outf(&mf1, &mf2, diffstat_consume, diffstat,
 +                            &xpp, &xecfg, &ecb);
        }
  
   free_and_return:
@@@ -1564,6 -1634,7 +1564,6 @@@ static void builtin_checkdiff(const cha
                return;
  
        memset(&data, 0, sizeof(data));
 -      data.xm.consume = checkdiff_consume;
        data.filename = name_b ? name_b : name_a;
        data.lineno = 0;
        data.o = o;
                xdemitconf_t xecfg;
                xdemitcb_t ecb;
  
 +              memset(&xpp, 0, sizeof(xpp));
                memset(&xecfg, 0, sizeof(xecfg));
                xecfg.ctxlen = 1; /* at least one context line */
                xpp.flags = XDF_NEED_MINIMAL;
 -              ecb.outf = xdiff_outf;
 -              ecb.priv = &data;
 -              xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 +              xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
 +                            &xpp, &xecfg, &ecb);
  
                if ((data.ws_rule & WS_TRAILING_SPACE) &&
                    data.trailing_blanks_start) {
@@@ -1616,7 -1687,6 +1616,7 @@@ struct diff_filespec *alloc_filespec(co
        spec->path = (char *)(spec + 1);
        memcpy(spec->path, path, namelen+1);
        spec->count = 1;
 +      spec->is_binary = -1;
        return spec;
  }
  
@@@ -1701,9 -1771,10 +1701,9 @@@ static int reuse_worktree_file(const ch
  
  static int populate_from_stdin(struct diff_filespec *s)
  {
 -      struct strbuf buf;
 +      struct strbuf buf = STRBUF_INIT;
        size_t size = 0;
  
 -      strbuf_init(&buf, 0);
        if (strbuf_read(&buf, 0, 0) < 0)
                return error("error while reading from stdin %s",
                                     strerror(errno));
@@@ -1755,7 -1826,7 +1755,7 @@@ int diff_populate_filespec(struct diff_
  
        if (!s->sha1_valid ||
            reuse_worktree_file(s->path, s->sha1, 0)) {
 -              struct strbuf buf;
 +              struct strbuf buf = STRBUF_INIT;
                struct stat st;
                int fd;
  
                s->size = xsize_t(st.st_size);
                if (!s->size)
                        goto empty;
 -              if (size_only)
 -                      return 0;
                if (S_ISLNK(st.st_mode)) {
 -                      int ret;
 -                      s->data = xmalloc(s->size);
 -                      s->should_free = 1;
 -                      ret = readlink(s->path, s->data, s->size);
 -                      if (ret < 0) {
 -                              free(s->data);
 +                      struct strbuf sb = STRBUF_INIT;
 +
 +                      if (strbuf_readlink(&sb, s->path, s->size))
                                goto err_empty;
 -                      }
 +                      s->size = sb.len;
 +                      s->data = strbuf_detach(&sb, NULL);
 +                      s->should_free = 1;
                        return 0;
                }
 +              if (size_only)
 +                      return 0;
                fd = open(s->path, O_RDONLY);
                if (fd < 0)
                        goto err_empty;
                /*
                 * Convert from working tree format to canonical git format
                 */
 -              strbuf_init(&buf, 0);
                if (convert_to_git(s->path, s->data, s->size, &buf, safe_crlf)) {
                        size_t size = 0;
                        munmap(s->data, s->size);
@@@ -1884,12 -1957,13 +1884,12 @@@ static void prepare_temp_file(const cha
                if (S_ISLNK(st.st_mode)) {
                        int ret;
                        char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
 -                      size_t sz = xsize_t(st.st_size);
 -                      if (sizeof(buf) <= st.st_size)
 -                              die("symlink too long: %s", name);
 -                      ret = readlink(name, buf, sz);
 +                      ret = readlink(name, buf, sizeof(buf));
                        if (ret < 0)
                                die("readlink(%s)", name);
 -                      prep_temp_blob(temp, buf, sz,
 +                      if (ret == sizeof(buf))
 +                              die("symlink too long: %s", name);
 +                      prep_temp_blob(temp, buf, ret,
                                       (one->sha1_valid ?
                                        one->sha1 : null_sha1),
                                       (one->sha1_valid ?
@@@ -1999,22 -2073,115 +1999,92 @@@ static void run_external_diff(const cha
        }
  }
  
 -static const char *external_diff_attr(const char *name)
 -{
 -      struct git_attr_check attr_diff_check;
 -
 -      if (!name)
 -              return NULL;
 -
 -      setup_diff_attr_check(&attr_diff_check);
 -      if (!git_checkattr(name, 1, &attr_diff_check)) {
 -              const char *value = attr_diff_check.value;
 -              if (!ATTR_TRUE(value) &&
 -                  !ATTR_FALSE(value) &&
 -                  !ATTR_UNSET(value)) {
 -                      struct ll_diff_driver *drv;
 -
 -                      for (drv = user_diff; drv; drv = drv->next)
 -                              if (!strcmp(drv->name, value))
 -                                      return drv->cmd;
 -              }
 -      }
 -      return NULL;
 -}
 -
+ static int similarity_index(struct diff_filepair *p)
+ {
+       return p->score * 100 / MAX_SCORE;
+ }
+ static void fill_metainfo(struct strbuf *msg,
+                         const char *name,
+                         const char *other,
+                         struct diff_filespec *one,
+                         struct diff_filespec *two,
+                         struct diff_options *o,
+                         struct diff_filepair *p)
+ {
+       strbuf_init(msg, PATH_MAX * 2 + 300);
+       switch (p->status) {
+       case DIFF_STATUS_COPIED:
+               strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
+               strbuf_addstr(msg, "\ncopy from ");
+               quote_c_style(name, msg, NULL, 0);
+               strbuf_addstr(msg, "\ncopy to ");
+               quote_c_style(other, msg, NULL, 0);
+               strbuf_addch(msg, '\n');
+               break;
+       case DIFF_STATUS_RENAMED:
+               strbuf_addf(msg, "similarity index %d%%", similarity_index(p));
+               strbuf_addstr(msg, "\nrename from ");
+               quote_c_style(name, msg, NULL, 0);
+               strbuf_addstr(msg, "\nrename to ");
+               quote_c_style(other, msg, NULL, 0);
+               strbuf_addch(msg, '\n');
+               break;
+       case DIFF_STATUS_MODIFIED:
+               if (p->score) {
+                       strbuf_addf(msg, "dissimilarity index %d%%\n",
+                                   similarity_index(p));
+                       break;
+               }
+               /* fallthru */
+       default:
+               /* nothing */
+               ;
+       }
+       if (one && two && hashcmp(one->sha1, two->sha1)) {
+               int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
+               if (DIFF_OPT_TST(o, BINARY)) {
+                       mmfile_t mf;
+                       if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
+                           (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
+                               abbrev = 40;
+               }
+               strbuf_addf(msg, "index %.*s..%.*s",
+                           abbrev, sha1_to_hex(one->sha1),
+                           abbrev, sha1_to_hex(two->sha1));
+               if (one->mode == two->mode)
+                       strbuf_addf(msg, " %06o", one->mode);
+               strbuf_addch(msg, '\n');
+       }
+       if (msg->len)
+               strbuf_setlen(msg, msg->len - 1);
+ }
  static void run_diff_cmd(const char *pgm,
                         const char *name,
                         const char *other,
                         const char *attr_path,
                         struct diff_filespec *one,
                         struct diff_filespec *two,
-                        const char *xfrm_msg,
+                        struct strbuf *msg,
                         struct diff_options *o,
-                        int complete_rewrite)
+                        struct diff_filepair *p)
  {
+       const char *xfrm_msg = NULL;
+       int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
+       if (msg) {
+               fill_metainfo(msg, name, other, one, two, o, p);
+               xfrm_msg = msg->len ? msg->buf : NULL;
+       }
        if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
                pgm = NULL;
        else {
 -              const char *cmd = external_diff_attr(attr_path);
 -              if (cmd)
 -                      pgm = cmd;
 +              struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
 +              if (drv && drv->external)
 +                      pgm = drv->external;
        }
  
        if (pgm) {
@@@ -2048,11 -2215,6 +2118,6 @@@ static void diff_fill_sha1_info(struct 
                hashclr(one->sha1);
  }
  
- static int similarity_index(struct diff_filepair *p)
- {
-       return p->score * 100 / MAX_SCORE;
- }
  static void strip_prefix(int prefix_length, const char **namep, const char **otherp)
  {
        /* Strip the prefix but do not molest /dev/null and absolute paths */
@@@ -2066,13 -2228,11 +2131,11 @@@ static void run_diff(struct diff_filepa
  {
        const char *pgm = external_diff();
        struct strbuf msg;
-       char *xfrm_msg;
        struct diff_filespec *one = p->one;
        struct diff_filespec *two = p->two;
        const char *name;
        const char *other;
        const char *attr_path;
-       int complete_rewrite = 0;
  
        name  = p->one->path;
        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
  
        if (DIFF_PAIR_UNMERGED(p)) {
                run_diff_cmd(pgm, name, NULL, attr_path,
-                            NULL, NULL, NULL, o, 0);
+                            NULL, NULL, NULL, o, p);
                return;
        }
  
        diff_fill_sha1_info(one);
        diff_fill_sha1_info(two);
  
-       strbuf_init(&msg, PATH_MAX * 2 + 300);
-       switch (p->status) {
-       case DIFF_STATUS_COPIED:
-               strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
-               strbuf_addstr(&msg, "\ncopy from ");
-               quote_c_style(name, &msg, NULL, 0);
-               strbuf_addstr(&msg, "\ncopy to ");
-               quote_c_style(other, &msg, NULL, 0);
-               strbuf_addch(&msg, '\n');
-               break;
-       case DIFF_STATUS_RENAMED:
-               strbuf_addf(&msg, "similarity index %d%%", similarity_index(p));
-               strbuf_addstr(&msg, "\nrename from ");
-               quote_c_style(name, &msg, NULL, 0);
-               strbuf_addstr(&msg, "\nrename to ");
-               quote_c_style(other, &msg, NULL, 0);
-               strbuf_addch(&msg, '\n');
-               break;
-       case DIFF_STATUS_MODIFIED:
-               if (p->score) {
-                       strbuf_addf(&msg, "dissimilarity index %d%%\n",
-                                       similarity_index(p));
-                       complete_rewrite = 1;
-                       break;
-               }
-               /* fallthru */
-       default:
-               /* nothing */
-               ;
-       }
-       if (hashcmp(one->sha1, two->sha1)) {
-               int abbrev = DIFF_OPT_TST(o, FULL_INDEX) ? 40 : DEFAULT_ABBREV;
-               if (DIFF_OPT_TST(o, BINARY)) {
-                       mmfile_t mf;
-                       if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
-                           (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
-                               abbrev = 40;
-               }
-               strbuf_addf(&msg, "index %.*s..%.*s",
-                               abbrev, sha1_to_hex(one->sha1),
-                               abbrev, sha1_to_hex(two->sha1));
-               if (one->mode == two->mode)
-                       strbuf_addf(&msg, " %06o", one->mode);
-               strbuf_addch(&msg, '\n');
-       }
-       if (msg.len)
-               strbuf_setlen(&msg, msg.len - 1);
-       xfrm_msg = msg.len ? msg.buf : NULL;
        if (!pgm &&
            DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
            (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
-               /* a filepair that changes between file and symlink
+               /*
+                * a filepair that changes between file and symlink
                 * needs to be split into deletion and creation.
                 */
                struct diff_filespec *null = alloc_filespec(two->path);
                run_diff_cmd(NULL, name, other, attr_path,
-                            one, null, xfrm_msg, o, 0);
+                            one, null, &msg, o, p);
                free(null);
+               strbuf_release(&msg);
                null = alloc_filespec(one->path);
                run_diff_cmd(NULL, name, other, attr_path,
-                            null, two, xfrm_msg, o, 0);
+                            null, two, &msg, o, p);
                free(null);
        }
        else
                run_diff_cmd(pgm, name, other, attr_path,
-                            one, two, xfrm_msg, o, complete_rewrite);
+                            one, two, &msg, o, p);
  
        strbuf_release(&msg);
  }
@@@ -2235,10 -2346,8 +2249,10 @@@ void diff_setup(struct diff_options *op
                DIFF_OPT_CLR(options, COLOR_DIFF);
        options->detect_rename = diff_detect_rename_default;
  
 -      options->a_prefix = "a/";
 -      options->b_prefix = "b/";
 +      if (!diff_mnemonic_prefix) {
 +              options->a_prefix = "a/";
 +              options->b_prefix = "b/";
 +      }
  }
  
  int diff_setup_done(struct diff_options *options)
@@@ -2395,10 -2504,6 +2409,10 @@@ int diff_opt_parse(struct diff_options 
        else if (!strcmp(arg, "--cumulative")) {
                options->output_format |= DIFF_FORMAT_DIRSTAT;
                DIFF_OPT_SET(options, DIRSTAT_CUMULATIVE);
 +      } else if (opt_arg(arg, 0, "dirstat-by-file",
 +                         &options->dirstat_percent)) {
 +              options->output_format |= DIFF_FORMAT_DIRSTAT;
 +              DIFF_OPT_SET(options, DIRSTAT_BY_FILE);
        }
        else if (!strcmp(arg, "--check"))
                options->output_format |= DIFF_FORMAT_CHECKDIFF;
                DIFF_OPT_SET(options, ALLOW_EXTERNAL);
        else if (!strcmp(arg, "--no-ext-diff"))
                DIFF_OPT_CLR(options, ALLOW_EXTERNAL);
 +      else if (!strcmp(arg, "--textconv"))
 +              DIFF_OPT_SET(options, ALLOW_TEXTCONV);
 +      else if (!strcmp(arg, "--no-textconv"))
 +              DIFF_OPT_CLR(options, ALLOW_TEXTCONV);
        else if (!strcmp(arg, "--ignore-submodules"))
                DIFF_OPT_SET(options, IGNORE_SUBMODULES);
  
@@@ -2959,7 -3060,8 +2973,7 @@@ static void diff_summary(FILE *file, st
  }
  
  struct patch_id_t {
 -      struct xdiff_emit_state xm;
 -      SHA_CTX *ctx;
 +      git_SHA_CTX *ctx;
        int patchlen;
  };
  
@@@ -2987,7 -3089,7 +3001,7 @@@ static void patch_id_consume(void *priv
  
        new_len = remove_space(line, len);
  
 -      SHA1_Update(data->ctx, line, new_len);
 +      git_SHA1_Update(data->ctx, line, new_len);
        data->patchlen += new_len;
  }
  
@@@ -2996,13 -3098,14 +3010,13 @@@ static int diff_get_patch_id(struct dif
  {
        struct diff_queue_struct *q = &diff_queued_diff;
        int i;
 -      SHA_CTX ctx;
 +      git_SHA_CTX ctx;
        struct patch_id_t data;
        char buffer[PATH_MAX * 4 + 20];
  
 -      SHA1_Init(&ctx);
 +      git_SHA1_Init(&ctx);
        memset(&data, 0, sizeof(struct patch_id_t));
        data.ctx = &ctx;
 -      data.xm.consume = patch_id_consume;
  
        for (i = 0; i < q->nr; i++) {
                xpparam_t xpp;
                struct diff_filepair *p = q->queue[i];
                int len1, len2;
  
 +              memset(&xpp, 0, sizeof(xpp));
                memset(&xecfg, 0, sizeof(xecfg));
                if (p->status == 0)
                        return error("internal diff status error");
                                        len2, p->two->path,
                                        len1, p->one->path,
                                        len2, p->two->path);
 -              SHA1_Update(&ctx, buffer, len1);
 +              git_SHA1_Update(&ctx, buffer, len1);
  
                xpp.flags = XDF_NEED_MINIMAL;
                xecfg.ctxlen = 3;
                xecfg.flags = XDL_EMIT_FUNCNAMES;
 -              ecb.outf = xdiff_outf;
 -              ecb.priv = &data;
 -              xdi_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
 +              xdi_diff_outf(&mf1, &mf2, patch_id_consume, &data,
 +                            &xpp, &xecfg, &ecb);
        }
  
 -      SHA1_Final(sha1, &ctx);
 +      git_SHA1_Final(sha1, &ctx);
        return 0;
  }
  
@@@ -3146,6 -3249,7 +3160,6 @@@ void diff_flush(struct diff_options *op
                struct diffstat_t diffstat;
  
                memset(&diffstat, 0, sizeof(struct diffstat_t));
 -              diffstat.xm.consume = diffstat_consume;
                for (i = 0; i < q->nr; i++) {
                        struct diff_filepair *p = q->queue[i];
                        if (check_pair_status(p))
@@@ -3442,34 -3546,3 +3456,34 @@@ void diff_unmerge(struct diff_options *
        fill_filespec(one, sha1, mode);
        diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
  }
 +
 +static char *run_textconv(const char *pgm, struct diff_filespec *spec,
 +              size_t *outsize)
 +{
 +      struct diff_tempfile temp;
 +      const char *argv[3];
 +      const char **arg = argv;
 +      struct child_process child;
 +      struct strbuf buf = STRBUF_INIT;
 +
 +      prepare_temp_file(spec->path, &temp, spec);
 +      *arg++ = pgm;
 +      *arg++ = temp.name;
 +      *arg = NULL;
 +
 +      memset(&child, 0, sizeof(child));
 +      child.argv = argv;
 +      child.out = -1;
 +      if (start_command(&child) != 0 ||
 +          strbuf_read(&buf, child.out, 0) < 0 ||
 +          finish_command(&child) != 0) {
 +              if (temp.name == temp.tmp_path)
 +                      unlink(temp.name);
 +              error("error running textconv command '%s'", pgm);
 +              return NULL;
 +      }
 +      if (temp.name == temp.tmp_path)
 +              unlink(temp.name);
 +
 +      return strbuf_detach(&buf, outsize);
 +}
diff --combined t/t4030-diff-textconv.sh
index 2f27a0ba9ec002b1a6e4d3bd0ed1dc7484d4d14e,0000000000000000000000000000000000000000..a3f0897a52ce2147388baeac6fc64d3b8501b516
mode 100755,000000..100755
--- /dev/null
@@@ -1,126 -1,0 +1,126 @@@
- index ad8b3d2..67be421
 +#!/bin/sh
 +
 +test_description='diff.*.textconv tests'
 +. ./test-lib.sh
 +
 +find_diff() {
 +      sed '1,/^index /d' | sed '/^-- $/,$d'
 +}
 +
 +cat >expect.binary <<'EOF'
 +Binary files a/file and b/file differ
 +EOF
 +
 +cat >expect.text <<'EOF'
 +--- a/file
 ++++ b/file
 +@@ -1 +1,2 @@
 + 0
 ++1
 +EOF
 +
 +cat >hexdump <<'EOF'
 +#!/bin/sh
 +perl -e '$/ = undef; $_ = <>; s/./ord($&)/ge; print $_' < "$1"
 +EOF
 +chmod +x hexdump
 +
 +test_expect_success 'setup binary file with history' '
 +      printf "\\0\\n" >file &&
 +      git add file &&
 +      git commit -m one &&
 +      printf "\\01\\n" >>file &&
 +      git add file &&
 +      git commit -m two
 +'
 +
 +test_expect_success 'file is considered binary by porcelain' '
 +      git diff HEAD^ HEAD >diff &&
 +      find_diff <diff >actual &&
 +      test_cmp expect.binary actual
 +'
 +
 +test_expect_success 'file is considered binary by plumbing' '
 +      git diff-tree -p HEAD^ HEAD >diff &&
 +      find_diff <diff >actual &&
 +      test_cmp expect.binary actual
 +'
 +
 +test_expect_success 'setup textconv filters' '
 +      echo file diff=foo >.gitattributes &&
 +      git config diff.foo.textconv "$PWD"/hexdump &&
 +      git config diff.fail.textconv false
 +'
 +
 +test_expect_success 'diff produces text' '
 +      git diff HEAD^ HEAD >diff &&
 +      find_diff <diff >actual &&
 +      test_cmp expect.text actual
 +'
 +
 +test_expect_success 'diff-tree produces binary' '
 +      git diff-tree -p HEAD^ HEAD >diff &&
 +      find_diff <diff >actual &&
 +      test_cmp expect.binary actual
 +'
 +
 +test_expect_success 'log produces text' '
 +      git log -1 -p >log &&
 +      find_diff <log >actual &&
 +      test_cmp expect.text actual
 +'
 +
 +test_expect_success 'format-patch produces binary' '
 +      git format-patch --no-binary --stdout HEAD^ >patch &&
 +      find_diff <patch >actual &&
 +      test_cmp expect.binary actual
 +'
 +
 +test_expect_success 'status -v produces text' '
 +      git reset --soft HEAD^ &&
 +      git status -v >diff &&
 +      find_diff <diff >actual &&
 +      test_cmp expect.text actual &&
 +      git reset --soft HEAD@{1}
 +'
 +
 +cat >expect.stat <<'EOF'
 + file |  Bin 2 -> 4 bytes
 + 1 files changed, 0 insertions(+), 0 deletions(-)
 +EOF
 +test_expect_success 'diffstat does not run textconv' '
 +      echo file diff=fail >.gitattributes &&
 +      git diff --stat HEAD^ HEAD >actual &&
 +      test_cmp expect.stat actual
 +'
 +# restore working setup
 +echo file diff=foo >.gitattributes
 +
 +cat >expect.typechange <<'EOF'
 +--- a/file
 ++++ /dev/null
 +@@ -1,2 +0,0 @@
 +-0
 +-1
 +diff --git a/file b/file
 +new file mode 120000
++index 0000000..67be421
 +--- /dev/null
 ++++ b/file
 +@@ -0,0 +1 @@
 ++frotz
 +\ No newline at end of file
 +EOF
 +# make a symlink the hard way that works on symlink-challenged file systems
 +test_expect_success 'textconv does not act on symlinks' '
 +      printf frotz > file &&
 +      git add file &&
 +      git ls-files -s | sed -e s/100644/120000/ |
 +              git update-index --index-info &&
 +      git commit -m typechange &&
 +      git show >diff &&
 +      find_diff <diff >actual &&
 +      test_cmp expect.typechange actual
 +'
 +
 +test_done