ChangeLog, subst.c, subst.conf.in:

  * subst.c: Add the ability to substitute apparent shell/make variables
  	such as ${prefix}, since this is needed to make the shell scripts work
  	correctly.
  subst.conf.in: Add ${prefix} to the list of substitutions which subst
  	should make.

diff --git a/util/ChangeLog b/util/ChangeLog
index a80bc06..05fb783 100644 (file)
--- a/util/ChangeLog
+++ b/util/ChangeLog
@@ -1,3 +1,12 @@
+1998-08-01  Theodore Ts'o  <tytso@rsts-11.mit.edu>
+
+       * subst.c: Add the ability to substitute apparent shell/make
+               variables such as ${prefix}, since this is needed to make
+               the shell scripts work correctly.
+
+       * subst.conf.in: Add ${prefix} to the list of substitutions which
+               subst should make.
+
 1998-07-09  Theodore Ts'o  <tytso@rsts-11.mit.edu>
 
        * Release of E2fsprogs 1.12

diff --git a/util/subst.c b/util/subst.c
index 588a4e3..9b9b176 100644 (file)
--- a/util/subst.c
+++ b/util/subst.c
@@ -67,24 +67,81 @@ static struct subst_entry *fetch_subst_entry(char *name)
        return ent;
 }
 
+/*
+ * Given the starting and ending position of the replacement name,
+ * check to see if it is valid, and pull it out if it is.
+ */
+static char *get_subst_symbol(const char *begin, int len, char prefix)
+{
+       static char replace_name[128];
+       char *cp, *start;
+
+       start = replace_name;
+       if (prefix)
+               *start++ = prefix;
+
+       if (len > sizeof(replace_name)-2)
+               return NULL;
+       memcpy(start, begin, len);
+       start[len] = 0;
+       
+       /*
+        * The substitution variable must all be in the of [A-Za-z_].
+        * If it isn't, this must be an invalid symbol name.
+        */
+       for (cp = start; *cp; cp++) {
+               if (!(*cp >= 'a' && *cp <= 'z') &&
+                   !(*cp >= 'A' && *cp <= 'Z') &&
+                   !(*cp == '_'))
+                       return NULL;
+       }
+       return (replace_name);
+}
+
+static void replace_string(char *begin, char *end, char *newstr)
+{
+       int     replace_len, len;
+
+       replace_len = strlen(newstr);
+       len = end - begin;
+       if (replace_len != len+1)
+               memmove(end+(replace_len-len-1), end,
+                       strlen(end)+1);
+       memcpy(begin, newstr, replace_len);
+}
+
 static void substitute_line(char *line)
 {
-       char    *ptr, *name_ptr, *end_ptr;
+       char    *ptr, *name_ptr, *end_ptr, *cp, ch;
        struct subst_entry *ent;
-       char    replace_name[128];
+       char    *replace_name;
        int     len, replace_len;
 
+       /*
+        * Expand all @FOO@ substitutions
+        */
        ptr = line;
        while (ptr) {
                name_ptr = strchr(ptr, '@');
                if (!name_ptr)
-                       break;
-               end_ptr = strchr(name_ptr+1, '@');
+                       break;  /* No more */
+               if (*(++name_ptr) == '@') {
+                       /*
+                        * Handle tytso@@mit.edu --> tytso@mit.edu
+                        */
+                       memmove(name_ptr-1, name_ptr, strlen(name_ptr)+1);
+                       ptr = name_ptr+1;
+                       continue;
+               }
+               end_ptr = strchr(name_ptr, '@');
                if (!end_ptr)
                        break;
-               len = end_ptr - name_ptr - 1;
-               memcpy(replace_name, name_ptr+1, len);
-               replace_name[len] = 0;
+               len = end_ptr - name_ptr;
+               replace_name = get_subst_symbol(name_ptr, len, 0);
+               if (!replace_name) {
+                       ptr = name_ptr;
+                       continue;
+               }
                ent = fetch_subst_entry(replace_name);
                if (!ent) {
                        fprintf(stderr, "Unfound expansion: '%s'\n", 
@@ -96,12 +153,42 @@ static void substitute_line(char *line)
                fprintf(stderr, "Replace name = '%s' with '%s'\n",
                       replace_name, ent->value);
 #endif
-               replace_len = strlen(ent->value);
-               if (replace_len != len+2)
-                       memmove(end_ptr+(replace_len-len-2), end_ptr,
-                               strlen(end_ptr)+1);
-               memcpy(name_ptr, ent->value, replace_len);
-               ptr = name_ptr;
+               ptr = name_ptr-1;
+               replace_string(ptr, end_ptr, ent->value);
+       }
+       /*
+        * Now do a second pass to expand ${FOO}
+        */
+       ptr = line;
+       while (ptr) {
+               name_ptr = strchr(ptr, '$');
+               if (!name_ptr)
+                       break;  /* No more */
+               if (*(++name_ptr) != '{') {
+                       ptr = name_ptr;
+                       continue;
+               }
+               name_ptr++;
+               end_ptr = strchr(name_ptr, '}');
+               if (!end_ptr)
+                       break;
+               len = end_ptr - name_ptr;
+               replace_name = get_subst_symbol(name_ptr, len, '$');
+               if (!replace_name) {
+                       ptr = name_ptr;
+                       continue;
+               }                       
+               ent = fetch_subst_entry(replace_name);
+               if (!ent) {
+                       ptr = end_ptr + 1;
+                       continue;
+               }
+#if 0
+               fprintf(stderr, "Replace name = '%s' with '%s'\n",
+                      replace_name, ent->value);
+#endif
+               ptr = name_ptr-2;
+               replace_string(ptr, end_ptr, ent->value);
        }
 }
 
@@ -144,7 +231,7 @@ static void parse_config_file(FILE *f)
                /*
                 * Ignore future extensions
                 */
-               if (*ptr == '$')
+               if (*ptr == '@')
                        continue;
                /*
                 * Parse substitutions

diff --git a/util/subst.conf.in b/util/subst.conf.in
index 355f169..c90ae6d 100644 (file)
--- a/util/subst.conf.in
+++ b/util/subst.conf.in
@@ -10,3 +10,4 @@ SIZEOF_LONG           @SIZEOF_LONG@
 SIZEOF_INT             @SIZEOF_INT@
 SIZEOF_SHORT           @SIZEOF_SHORT@
 datadir                        @datadir@
+$prefix                        @prefix@