--pretty=format: on-demand format expansion

[thirdparty/git.git] / strbuf.c

diff --git a/strbuf.c b/strbuf.c
index f4201e160de2ccb9f2d9adef695c73a124e676d5..536b43204e228a8b7ec8fc3fb44c555157253f8c 100644 (file)
--- a/strbuf.c
+++ b/strbuf.c
@@ -129,6 +129,30 @@ void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
        strbuf_setlen(sb, sb->len + len);
 }
 
+void strbuf_expand(struct strbuf *sb, const char *format,
+                   const char **placeholders, expand_fn_t fn, void *context)
+{
+       for (;;) {
+               const char *percent, **p;
+
+               percent = strchrnul(format, '%');
+               strbuf_add(sb, format, percent - format);
+               if (!*percent)
+                       break;
+               format = percent + 1;
+
+               for (p = placeholders; *p; p++) {
+                       if (!prefixcmp(format, *p))
+                               break;
+               }
+               if (*p) {
+                       fn(sb, *p, context);
+                       format += strlen(*p);
+               } else
+                       strbuf_addch(sb, '%');
+       }
+}
+
 size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
 {
        size_t res;