- djm@cvs.openbsd.org 2005/06/06 11:20:36

     [auth.c auth.h misc.c misc.h ssh.c ssh_config.5 sshconnect.c]
     introduce a generic %foo expansion function. replace existing % expansion
     and add expansion to ControlPath; ok markus@

1 files changed, 64 insertions, 1 deletions

diff --git a/misc.c b/misc.c
index 4bc07a42a..fc094f874 100644
--- a/misc.c
+++ b/misc.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
+ * Copyright (c) 2005 Damien Miller.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -23,7 +24,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: misc.c,v 1.30 2005/04/09 04:32:54 djm Exp $");
+RCSID("$OpenBSD: misc.c,v 1.31 2005/06/06 11:20:36 djm Exp $");
 
 #include "misc.h"
 #include "log.h"
@@ -421,6 +422,68 @@ tilde_expand_filename(const char *filename, uid_t uid)
 }
 
 /*
+ * Expand a string with a set of %[char] escapes. A number of escapes may be
+ * specified as (char *escape_chars, char *replacement) pairs. The list must
+ * be terminated by an escape_char of -1. Returns replaced string in memory
+ * allocated by xmalloc.
+ */
+char *
+percent_expand(const char *string, ...)
+{
+#define EXPAND_MAX_KEYS 16
+        struct {
+                const char *key;
+                const char *repl;
+        } keys[EXPAND_MAX_KEYS];
+        int num_keys, i, j;
+        char buf[4096];
+        va_list ap;
+
+        /* Gather keys */
+        va_start(ap, string);
+        for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
+                keys[num_keys].key = va_arg(ap, char *);
+                if (keys[num_keys].key == NULL)
+                        break;
+                keys[num_keys].repl = va_arg(ap, char *);
+                if (keys[num_keys].repl == NULL)
+                        fatal("percent_expand: NULL replacement");
+        }
+        va_end(ap);
+
+        if (num_keys >= EXPAND_MAX_KEYS)
+                fatal("percent_expand: too many keys");
+
+        /* Expand string */
+        *buf = '\0';
+        for (i = 0; *string != '\0'; string++) {
+                if (*string != '%') {
+ append:
+                        buf[i++] = *string;
+                        if (i >= sizeof(buf))
+                                fatal("percent_expand: string too long");
+                        buf[i] = '\0';
+                        continue;
+                }
+                string++;
+                if (*string == '%')
+                        goto append;
+                for (j = 0; j < num_keys; j++) {
+                        if (strchr(keys[j].key, *string) != NULL) {
+                                i = strlcat(buf, keys[j].repl, sizeof(buf));
+                                if (i >= sizeof(buf))
+                                        fatal("percent_expand: string too long");
+                                break;
+                        }
+                }
+                if (j >= num_keys)
+                        fatal("percent_expand: unknown key %%%c", *string);
+        }
+        return (xstrdup(buf));
+#undef EXPAND_MAX_KEYS
+}
+
+/*
  * Read an entire line from a public key file into a static buffer, discarding
  * lines that exceed the buffer size.  Returns 0 on success, -1 on failure.
  */