+/*************************************************
+* Deal with an assignment to a macro *
+*************************************************/
+
+/* This function is called when a line that starts with an upper case letter is
+encountered. The argument "line" should contain a complete logical line, and
+start with the first letter of the macro name. The macro name and the
+replacement text are extracted and stored. Redefinition of existing,
+non-command line, macros is permitted using '==' instead of '='.
+
+Arguments:
+ s points to the start of the logical line
+
+Returns: nothing
+*/
+
+static void
+read_macro_assignment(uschar *s)
+{
+uschar name[64];
+int namelen = 0;
+BOOL redef = FALSE;
+macro_item *m;
+macro_item *mlast = NULL;
+
+while (isalnum(*s) || *s == '_')
+ {
+ if (namelen >= sizeof(name) - 1)
+ log_write(0, LOG_PANIC_DIE|LOG_CONFIG_IN,
+ "macro name too long (maximum is " SIZE_T_FMT " characters)", sizeof(name) - 1);
+ name[namelen++] = *s++;
+ }
+name[namelen] = 0;
+
+while (isspace(*s)) s++;
+if (*s++ != '=')
+ log_write(0, LOG_PANIC_DIE|LOG_CONFIG_IN, "malformed macro definition");
+
+if (*s == '=')
+ {
+ redef = TRUE;
+ s++;
+ }
+while (isspace(*s)) s++;
+
+/* If an existing macro of the same name was defined on the command line, we
+just skip this definition. It's an error to attempt to redefine a macro without
+redef set to TRUE, or to redefine a macro when it hasn't been defined earlier.
+It is also an error to define a macro whose name begins with the name of a
+previously defined macro. Note: it is documented that the other way round
+works. */
+
+for (m = macros; m != NULL; m = m->next)
+ {
+ int len = Ustrlen(m->name);
+
+ if (Ustrcmp(m->name, name) == 0)
+ {
+ if (!m->command_line && !redef)
+ log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "macro \"%s\" is already "
+ "defined (use \"==\" if you want to redefine it", name);
+ break;
+ }
+
+ if (len < namelen && Ustrstr(name, m->name) != NULL)
+ log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "\"%s\" cannot be defined as "
+ "a macro because previously defined macro \"%s\" is a substring",
+ name, m->name);
+
+ /* We cannot have this test, because it is documented that a substring
+ macro is permitted (there is even an example).
+ *
+ * if (len > namelen && Ustrstr(m->name, name) != NULL)
+ * log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "\"%s\" cannot be defined as "
+ * "a macro because it is a substring of previously defined macro \"%s\"",
+ * name, m->name);
+ */
+
+ mlast = m;
+ }
+
+/* Check for an overriding command-line definition. */
+
+if (m != NULL && m->command_line) return;
+
+/* Redefinition must refer to an existing macro. */
+
+if (redef)
+ {
+ if (m == NULL)
+ log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "can't redefine an undefined macro "
+ "\"%s\"", name);
+ }
+
+/* We have a new definition. The macro_item structure includes a final vector
+called "name" which is one byte long. Thus, adding "namelen" gives us enough
+room to store the "name" string. */
+
+else
+ {
+ m = store_get(sizeof(macro_item) + namelen);
+ if (macros == NULL) macros = m; else mlast->next = m;
+ Ustrncpy(m->name, name, namelen);
+ m->name[namelen] = 0;
+ m->next = NULL;
+ m->command_line = FALSE;
+ }
+
+/* Set the value of the new or redefined macro */
+
+m->replacement = string_copy(s);
+}
+
+
+
+
projects / exim.git / blobdiff