config: make parsing stack struct independent from actual data source

To simplify adding other sources we extract all functions needed for
parsing into a list of callbacks. We implement those callbacks for the
current file parsing. A new source can implement its own set of callbacks.

Instead of storing the concrete FILE pointer for parsing we store a void
pointer. A new source can use this to store its custom data.

Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/config.c b/config.c
index 046642b69f1791373593403ad873b67ed764885f..fc2796771b689e85daf0a400488eeae3f7a48cd9 100644 (file)
--- a/config.c
+++ b/config.c
@@ -10,20 +10,41 @@
 #include "strbuf.h"
 #include "quote.h"
 
 #include "strbuf.h"
 #include "quote.h"
 

-typedef struct config_file {
-       struct config_file *prev;
-       FILE *f;
+struct config_source {
+       struct config_source *prev;
+       union {
+               FILE *file;
+       } u;

        const char *name;
        int linenr;
        int eof;
        struct strbuf value;
        struct strbuf var;
        const char *name;
        int linenr;
        int eof;
        struct strbuf value;
        struct strbuf var;

-} config_file;

 
 

-static config_file *cf;
+       int (*fgetc)(struct config_source *c);
+       int (*ungetc)(int c, struct config_source *conf);
+       long (*ftell)(struct config_source *c);
+};
+
+static struct config_source *cf;

 
 static int zlib_compression_seen;
 
 
 static int zlib_compression_seen;
 

+static int config_file_fgetc(struct config_source *conf)
+{
+       return fgetc(conf->u.file);
+}
+
+static int config_file_ungetc(int c, struct config_source *conf)
+{
+       return ungetc(c, conf->u.file);
+}
+
+static long config_file_ftell(struct config_source *conf)
+{
+       return ftell(conf->u.file);
+}
+

 #define MAX_INCLUDE_DEPTH 10
 static const char include_depth_advice[] =
 "exceeded maximum include depth (%d) while including\n"
 #define MAX_INCLUDE_DEPTH 10
 static const char include_depth_advice[] =
 "exceeded maximum include depth (%d) while including\n"


@@ -168,15 +189,13 @@ int git_config_from_parameters(config_fn_t fn, void *data)
 
 static int get_next_char(void)
 {
 
 static int get_next_char(void)
 {

-       int c;
-       FILE *f = cf->f;
+       int c = cf->fgetc(cf);

 
 

-       c = fgetc(f);

        if (c == '\r') {
                /* DOS like systems */
        if (c == '\r') {
                /* DOS like systems */

-               c = fgetc(f);
+               c = cf->fgetc(cf);

                if (c != '\n') {
                if (c != '\n') {

-                       ungetc(c, f);
+                       cf->ungetc(c, cf);

                        c = '\r';
                }
        }
                        c = '\r';
                }
        }


@@ -336,7 +355,7 @@ static int get_base_var(struct strbuf *name)
        }
 }
 
        }
 }
 

-static int git_parse_file(config_fn_t fn, void *data)
+static int git_parse_source(config_fn_t fn, void *data)

 {
        int comment = 0;
        int baselen = 0;
 {
        int comment = 0;
        int baselen = 0;


@@ -894,10 +913,11 @@ int git_default_config(const char *var, const char *value, void *dummy)
 }
 
 /*
 }
 
 /*

- * The fields f and name of top need to be initialized before calling
+ * All source specific fields in the union, name and the callbacks
+ * fgetc, ungetc, ftell of top need to be initialized before calling

  * this function.
  */
  * this function.
  */

-static int do_config_from(struct config_file *top, config_fn_t fn, void *data)
+static int do_config_from(struct config_source *top, config_fn_t fn, void *data)

 {
        int ret;
 
 {
        int ret;
 


@@ -909,7 +929,7 @@ static int do_config_from(struct config_file *top, config_fn_t fn, void *data)
        strbuf_init(&top->var, 1024);
        cf = top;
 
        strbuf_init(&top->var, 1024);
        cf = top;
 

-       ret = git_parse_file(fn, data);
+       ret = git_parse_source(fn, data);

 
        /* pop config-file parsing state stack */
        strbuf_release(&top->value);
 
        /* pop config-file parsing state stack */
        strbuf_release(&top->value);


@@ -926,10 +946,13 @@ int git_config_from_file(config_fn_t fn, const char *filename, void *data)
 
        ret = -1;
        if (f) {
 
        ret = -1;
        if (f) {

-               config_file top;
+               struct config_source top;

 
 

-               top.f = f;
+               top.u.file = f;

                top.name = filename;
                top.name = filename;

+               top.fgetc = config_file_fgetc;
+               top.ungetc = config_file_ungetc;
+               top.ftell = config_file_ftell;

 
                ret = do_config_from(&top, fn, data);
 
 
                ret = do_config_from(&top, fn, data);
 


@@ -1064,7 +1087,6 @@ static int store_aux(const char *key, const char *value, void *cb)
 {
        const char *ep;
        size_t section_len;
 {
        const char *ep;
        size_t section_len;

-       FILE *f = cf->f;

 
        switch (store.state) {
        case KEY_SEEN:
 
        switch (store.state) {
        case KEY_SEEN:


@@ -1076,7 +1098,7 @@ static int store_aux(const char *key, const char *value, void *cb)
                                return 1;
                        }
 
                                return 1;
                        }
 

-                       store.offset[store.seen] = ftell(f);
+                       store.offset[store.seen] = cf->ftell(cf);

                        store.seen++;
                }
                break;
                        store.seen++;
                }
                break;


@@ -1103,19 +1125,19 @@ static int store_aux(const char *key, const char *value, void *cb)
                 * Do not increment matches: this is no match, but we
                 * just made sure we are in the desired section.
                 */
                 * Do not increment matches: this is no match, but we
                 * just made sure we are in the desired section.
                 */

-               store.offset[store.seen] = ftell(f);
+               store.offset[store.seen] = cf->ftell(cf);

                /* fallthru */
        case SECTION_END_SEEN:
        case START:
                if (matches(key, value)) {
                /* fallthru */
        case SECTION_END_SEEN:
        case START:
                if (matches(key, value)) {

-                       store.offset[store.seen] = ftell(f);
+                       store.offset[store.seen] = cf->ftell(cf);

                        store.state = KEY_SEEN;
                        store.seen++;
                } else {
                        if (strrchr(key, '.') - key == store.baselen &&
                              !strncmp(key, store.key, store.baselen)) {
                                        store.state = SECTION_SEEN;
                        store.state = KEY_SEEN;
                        store.seen++;
                } else {
                        if (strrchr(key, '.') - key == store.baselen &&
                              !strncmp(key, store.key, store.baselen)) {
                                        store.state = SECTION_SEEN;

-                                       store.offset[store.seen] = ftell(f);
+                                       store.offset[store.seen] = cf->ftell(cf);

                        }
                }
        }
                        }
                }
        }