Merge branch 'jk/diff-convfilter'
authorJunio C Hamano <gitster@pobox.com>
Wed, 22 Oct 2008 00:58:25 +0000 (17:58 -0700)
committerJunio C Hamano <gitster@pobox.com>
Wed, 22 Oct 2008 00:58:25 +0000 (17:58 -0700)
* jk/diff-convfilter:
diff: add filter for converting binary to text
diff: introduce diff.<driver>.binary
diff: unify external diff and funcname parsing code
t4012: use test_cmp instead of cmp

Makefile
diff.c
diffcore.h
t/t4012-diff-binary.sh
userdiff.c [new file with mode: 0644]
userdiff.h [new file with mode: 0644]
index 308dc70b5de118083a14bcb2665372a40ae6522c..d6f3695c97d5c36fe3b99dfc056173b6d785cd4b 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -389,6 +389,7 @@ LIB_H += transport.h
 LIB_H += tree.h
 LIB_H += tree-walk.h
 LIB_H += unpack-trees.h
+LIB_H += userdiff.h
 LIB_H += utf8.h
 LIB_H += wt-status.h
 
@@ -485,6 +486,7 @@ LIB_OBJS += tree-diff.o
 LIB_OBJS += tree.o
 LIB_OBJS += tree-walk.o
 LIB_OBJS += unpack-trees.o
+LIB_OBJS += userdiff.o
 LIB_OBJS += usage.o
 LIB_OBJS += utf8.o
 LIB_OBJS += walker.o
diff --git a/diff.c b/diff.c
index 1c6be897b2c95fc481c02834e4fe022b6bd405ae..e368fef14fdccf63fc3525349841ae93aea93046 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -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
@@ -37,6 +38,9 @@ static char diff_colors[][COLOR_MAXLEN] = {
        "\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"))
@@ -56,80 +60,6 @@ static int parse_diff_color_slot(const char *var, int ofs)
        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
@@ -162,11 +92,11 @@ int git_diff_ui_config(const char *var, const char *value, void *cb)
        }
        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);
+       switch (userdiff_config_porcelain(var, value)) {
+               case 0: break;
+               case -1: return -1;
+               default: return 0;
        }
 
        return git_diff_basic_config(var, value, cb);
@@ -193,21 +123,10 @@ int git_diff_basic_config(const char *var, const char *value, void *cb)
                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);
-                       }
-               }
+       switch (userdiff_config_basic(var, value)) {
+               case 0: break;
+               case -1: return -1;
+               default: return 0;
        }
 
        return git_color_default_config(var, value, cb);
@@ -374,8 +293,19 @@ 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;
+
+       diff_filespec_load_driver(one);
+       if (one->driver->textconv) {
+               size_t size;
+               mf->ptr = run_textconv(one->driver->textconv, one, &size);
+               if (!mf->ptr)
+                       return -1;
+               mf->size = size;
+       }
+       else {
+               mf->ptr = one->data;
+               mf->size = one->size;
+       }
        return 0;
 }
 
@@ -1352,136 +1282,37 @@ static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two)
        emit_binary_diff_body(file, two, one);
 }
 
-static void setup_diff_attr_check(struct git_attr_check *check)
+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;
-}
-
-static void diff_filespec_check_attr(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->driver)
+               one->driver = userdiff_find_by_path(one->path);
+       if (!one->driver)
+               one->driver = userdiff_find_by_name("default");
 }
 
 int diff_filespec_is_binary(struct diff_filespec *one)
 {
-       diff_filespec_check_attr(one);
+       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;
 }
 
-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[] = {
-       { "bibtex", "(@[a-zA-Z]{1,}[ \t]*\\{{0,1}[ \t]*[^ \t\"@',\\#}{~%]*).*$",
-         REG_EXTENDED },
-       { "html", "^[ \t]*(<[Hh][1-6][ \t].*>.*)$", REG_EXTENDED },
-       { "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]*\\([^;]*)$",
-         REG_EXTENDED },
-       { "objc",
-         /* Negate C statements that can look like functions */
-         "!^[ \t]*(do|for|if|else|return|switch|while)\n"
-         /* Objective-C methods */
-         "^[ \t]*([-+][ \t]*\\([ \t]*[A-Za-z_][A-Za-z_0-9* \t]*\\)[ \t]*[A-Za-z_].*)$\n"
-         /* C functions */
-         "^[ \t]*(([ \t]*[A-Za-z_][A-Za-z_0-9]*){2,}[ \t]*\\([^;]*)$\n"
-         /* Objective-C class/protocol definitions */
-         "^(@(implementation|interface|protocol)[ \t].*)$",
-         REG_EXTENDED },
-       { "pascal",
-         "^((procedure|function|constructor|destructor|interface|"
-               "implementation|initialization|finalization)[ \t]*.*)$"
-         "\n"
-         "^(.*=[ \t]*(class|record).*)$",
-         REG_EXTENDED },
-       { "php", "^[\t ]*((function|class).*)", REG_EXTENDED },
-       { "python", "^[ \t]*((class|def)[ \t].*)$", REG_EXTENDED },
-       { "ruby", "^[ \t]*((class|module|def)[ \t].*)$",
-         REG_EXTENDED },
-       { "tex",
-         "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$",
-         REG_EXTENDED },
-};
-
-static const struct funcname_pattern_entry *diff_funcname_pattern(struct diff_filespec *one)
+static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespec *one)
 {
-       const char *ident;
-       const struct funcname_pattern_entry *pe;
-       int i;
-
-       diff_filespec_check_attr(one);
-       ident = one->funcname_pattern_ident;
-
-       if (!ident)
-               /*
-                * If the config file has "funcname.default" defined, that
-                * regexp is used; otherwise NULL is returned and xemit uses
-                * the built-in default.
-                */
-               return funcname_pattern("default");
-
-       /* Look up custom "funcname.$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];
-
-       return NULL;
+       diff_filespec_load_driver(one);
+       return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
 }
 
 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
@@ -1579,7 +1410,7 @@ static void builtin_diff(const char *name_a,
                xdemitconf_t xecfg;
                xdemitcb_t ecb;
                struct emit_callback ecbdata;
-               const struct funcname_pattern_entry *pe;
+               const struct userdiff_funcname *pe;
 
                pe = diff_funcname_pattern(one);
                if (!pe)
@@ -1733,6 +1564,7 @@ struct diff_filespec *alloc_filespec(const char *path)
        spec->path = (char *)(spec + 1);
        memcpy(spec->path, path, namelen+1);
        spec->count = 1;
+       spec->is_binary = -1;
        return spec;
 }
 
@@ -2117,29 +1949,6 @@ static void run_external_diff(const char *pgm,
        }
 }
 
-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 void run_diff_cmd(const char *pgm,
                         const char *name,
                         const char *other,
@@ -2153,9 +1962,9 @@ static void run_diff_cmd(const char *pgm,
        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) {
@@ -3578,3 +3387,34 @@ void diff_unmerge(struct diff_options *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);
+}
index 8ae35785fd4439f466620ab9186838e7cb20fa36..713cca785c4b986b5f667086ad43c324f248929c 100644 (file)
@@ -22,6 +22,8 @@
 
 #define MINIMUM_BREAK_SIZE     400 /* do not break a file smaller than this */
 
+struct userdiff_driver;
+
 struct diff_filespec {
        unsigned char sha1[20];
        char *path;
@@ -40,8 +42,10 @@ struct diff_filespec {
 #define DIFF_FILE_VALID(spec) (((spec)->mode) != 0)
        unsigned should_free : 1; /* data should be free()'ed */
        unsigned should_munmap : 1; /* data should be munmap()'ed */
-       unsigned checked_attr : 1;
-       unsigned is_binary : 1; /* data should be considered "binary" */
+
+       struct userdiff_driver *driver;
+       /* data should be considered "binary"; -1 means "don't know yet" */
+       int is_binary;
 };
 
 extern struct diff_filespec *alloc_filespec(const char *);
index 421f4bba3fbc666cf2ab7ec4289f10d29d61eebb..3cf5b5c4ea05d861d75aa146a52d7d273dcaa4cb 100755 (executable)
@@ -25,11 +25,11 @@ cat > expected <<\EOF
 EOF
 test_expect_success 'diff without --binary' \
        'git diff | git apply --stat --summary >current &&
-        cmp current expected'
+        test_cmp expected current'
 
 test_expect_success 'diff with --binary' \
        'git diff --binary | git apply --stat --summary >current &&
-        cmp current expected'
+        test_cmp expected current'
 
 # apply needs to be able to skip the binary material correctly
 # in order to report the line number of a corrupt patch.
diff --git a/userdiff.c b/userdiff.c
new file mode 100644 (file)
index 0000000..d95257a
--- /dev/null
@@ -0,0 +1,175 @@
+#include "userdiff.h"
+#include "cache.h"
+#include "attr.h"
+
+static struct userdiff_driver *drivers;
+static int ndrivers;
+static int drivers_alloc;
+
+#define FUNCNAME(name, pattern) \
+       { name, NULL, -1, { pattern, REG_EXTENDED } }
+static struct userdiff_driver builtin_drivers[] = {
+FUNCNAME("html", "^[ \t]*(<[Hh][1-6][ \t].*>.*)$"),
+FUNCNAME("java",
+        "!^[ \t]*(catch|do|for|if|instanceof|new|return|switch|throw|while)\n"
+        "^[ \t]*(([ \t]*[A-Za-z_][A-Za-z_0-9]*){2,}[ \t]*\\([^;]*)$"),
+FUNCNAME("objc",
+        /* Negate C statements that can look like functions */
+        "!^[ \t]*(do|for|if|else|return|switch|while)\n"
+        /* Objective-C methods */
+        "^[ \t]*([-+][ \t]*\\([ \t]*[A-Za-z_][A-Za-z_0-9* \t]*\\)[ \t]*[A-Za-z_].*)$\n"
+        /* C functions */
+        "^[ \t]*(([ \t]*[A-Za-z_][A-Za-z_0-9]*){2,}[ \t]*\\([^;]*)$\n"
+        /* Objective-C class/protocol definitions */
+        "^(@(implementation|interface|protocol)[ \t].*)$"),
+FUNCNAME("pascal",
+        "^((procedure|function|constructor|destructor|interface|"
+               "implementation|initialization|finalization)[ \t]*.*)$"
+        "\n"
+        "^(.*=[ \t]*(class|record).*)$"),
+FUNCNAME("php", "^[\t ]*((function|class).*)"),
+FUNCNAME("python", "^[ \t]*((class|def)[ \t].*)$"),
+FUNCNAME("ruby", "^[ \t]*((class|module|def)[ \t].*)$"),
+FUNCNAME("bibtex", "(@[a-zA-Z]{1,}[ \t]*\\{{0,1}[ \t]*[^ \t\"@',\\#}{~%]*).*$"),
+FUNCNAME("tex", "^(\\\\((sub)*section|chapter|part)\\*{0,1}\\{.*)$"),
+{ "default", NULL, -1, { NULL, 0 } },
+};
+#undef FUNCNAME
+
+static struct userdiff_driver driver_true = {
+       "diff=true",
+       NULL,
+       0,
+       { NULL, 0 }
+};
+
+static struct userdiff_driver driver_false = {
+       "!diff",
+       NULL,
+       1,
+       { NULL, 0 }
+};
+
+static struct userdiff_driver *userdiff_find_by_namelen(const char *k, int len)
+{
+       int i;
+       for (i = 0; i < ndrivers; i++) {
+               struct userdiff_driver *drv = drivers + i;
+               if (!strncmp(drv->name, k, len) && !drv->name[len])
+                       return drv;
+       }
+       for (i = 0; i < ARRAY_SIZE(builtin_drivers); i++) {
+               struct userdiff_driver *drv = builtin_drivers + i;
+               if (!strncmp(drv->name, k, len) && !drv->name[len])
+                       return drv;
+       }
+       return NULL;
+}
+
+static struct userdiff_driver *parse_driver(const char *var,
+               const char *value, const char *type)
+{
+       struct userdiff_driver *drv;
+       const char *dot;
+       const char *name;
+       int namelen;
+
+       if (prefixcmp(var, "diff."))
+               return NULL;
+       dot = strrchr(var, '.');
+       if (dot == var + 4)
+               return NULL;
+       if (strcmp(type, dot+1))
+               return NULL;
+
+       name = var + 5;
+       namelen = dot - name;
+       drv = userdiff_find_by_namelen(name, namelen);
+       if (!drv) {
+               ALLOC_GROW(drivers, ndrivers+1, drivers_alloc);
+               drv = &drivers[ndrivers++];
+               memset(drv, 0, sizeof(*drv));
+               drv->name = xmemdupz(name, namelen);
+               drv->binary = -1;
+       }
+       return drv;
+}
+
+static int parse_funcname(struct userdiff_funcname *f, const char *k,
+               const char *v, int cflags)
+{
+       if (git_config_string(&f->pattern, k, v) < 0)
+               return -1;
+       f->cflags = cflags;
+       return 1;
+}
+
+static int parse_string(const char **d, const char *k, const char *v)
+{
+       if (git_config_string(d, k, v) < 0)
+               return -1;
+       return 1;
+}
+
+static int parse_tristate(int *b, const char *k, const char *v)
+{
+       if (v && !strcasecmp(v, "auto"))
+               *b = -1;
+       else
+               *b = git_config_bool(k, v);
+       return 1;
+}
+
+int userdiff_config_basic(const char *k, const char *v)
+{
+       struct userdiff_driver *drv;
+
+       if ((drv = parse_driver(k, v, "funcname")))
+               return parse_funcname(&drv->funcname, k, v, 0);
+       if ((drv = parse_driver(k, v, "xfuncname")))
+               return parse_funcname(&drv->funcname, k, v, REG_EXTENDED);
+       if ((drv = parse_driver(k, v, "binary")))
+               return parse_tristate(&drv->binary, k, v);
+
+       return 0;
+}
+
+int userdiff_config_porcelain(const char *k, const char *v)
+{
+       struct userdiff_driver *drv;
+
+       if ((drv = parse_driver(k, v, "command")))
+               return parse_string(&drv->external, k, v);
+       if ((drv = parse_driver(k, v, "textconv")))
+               return parse_string(&drv->textconv, k, v);
+
+       return 0;
+}
+
+struct userdiff_driver *userdiff_find_by_name(const char *name) {
+       int len = strlen(name);
+       return userdiff_find_by_namelen(name, len);
+}
+
+struct userdiff_driver *userdiff_find_by_path(const char *path)
+{
+       static struct git_attr *attr;
+       struct git_attr_check check;
+
+       if (!attr)
+               attr = git_attr("diff", 4);
+       check.attr = attr;
+
+       if (!path)
+               return NULL;
+       if (git_checkattr(path, 1, &check))
+               return NULL;
+
+       if (ATTR_TRUE(check.value))
+               return &driver_true;
+       if (ATTR_FALSE(check.value))
+               return &driver_false;
+       if (ATTR_UNSET(check.value))
+               return NULL;
+       return userdiff_find_by_name(check.value);
+}
diff --git a/userdiff.h b/userdiff.h
new file mode 100644 (file)
index 0000000..f29c18f
--- /dev/null
@@ -0,0 +1,22 @@
+#ifndef USERDIFF_H
+#define USERDIFF_H
+
+struct userdiff_funcname {
+       const char *pattern;
+       int cflags;
+};
+
+struct userdiff_driver {
+       const char *name;
+       const char *external;
+       int binary;
+       struct userdiff_funcname funcname;
+       const char *textconv;
+};
+
+int userdiff_config_basic(const char *k, const char *v);
+int userdiff_config_porcelain(const char *k, const char *v);
+struct userdiff_driver *userdiff_find_by_name(const char *name);
+struct userdiff_driver *userdiff_find_by_path(const char *path);
+
+#endif /* USERDIFF */