stuff from chiark:/usr/local/src/misc/ (as found)

[chiark-utils.git] / cprogs / myopt.c

diff --git a/cprogs/myopt.c b/cprogs/myopt.c
new file mode 100644 (file)
index 0000000..ab89df8
--- /dev/null
+++ b/cprogs/myopt.c
@@ -0,0 +1,96 @@
+/*
+ * libdpkg - Debian packaging suite library routines
+ * myopt.c - my very own option parsing
+ *
+ * Copyright (C) 1994,1995 Ian Jackson <iwj10@cus.cam.ac.uk>
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2,
+ * or (at your option) any later version.
+ *
+ * This is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this file; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdlib.h>
+
+#include "myopt.h"
+
+void badusage(const char *fmt, ...) {
+  va_list al;
+  
+  va_start(al,fmt);
+  vfprintf(stderr,fmt,al);
+  va_end(al);
+  fputc('\n',stderr);
+  usagemessage();
+  exit(-1);
+}
+
+void myopt(const char *const **argvp, const struct cmdinfo *cmdinfos) {
+  const struct cmdinfo *cip;
+  const char *p, *value;
+  int l;
+
+  ++(*argvp);
+  while ((p= **argvp) && *p == '-') {
+    ++(*argvp);
+    if (!strcmp(p,"--")) break;
+    if (*++p == '-') {
+      ++p; value=0;
+      for (cip= cmdinfos;
+           cip->olong || cip->oshort;
+           cip++) {
+        if (!cip->olong) continue;
+        if (!strcmp(p,cip->olong)) break;
+        l= strlen(cip->olong);
+        if (!strncmp(p,cip->olong,l) &&
+            (p[l]== ((cip->takesvalue==2) ? '-' : '='))) { value=p+l+1; break; }
+      }
+      if (!cip->olong) badusage("unknown option --%s",p);
+      if (cip->takesvalue) {
+        if (!value) {
+          value= *(*argvp)++;
+          if (!value) badusage("--%s option takes a value",cip->olong);
+        }
+        if (cip->call) cip->call(cip,value);
+        else *cip->sassignto= value;
+      } else {
+        if (value) badusage("--%s option does not take a value",cip->olong);
+        if (cip->call) cip->call(cip,0);
+        else *cip->iassignto= cip->arg;
+      }
+    } else {
+      while (*p) {
+        for (cip= cmdinfos; (cip->olong || cip->oshort) && *p != cip->oshort; cip++);
+        if (!cip->oshort) badusage("unknown option -%c",*p);
+        p++;
+        if (cip->takesvalue) {
+          if (!*p) {
+            value= *(*argvp)++;
+            if (!value) badusage("-%c option takes a value",cip->oshort);
+          } else {
+            value= p; p="";
+            if (*value == '=') value++;
+          }
+          if (cip->call) cip->call(cip,value);
+          else *cip->sassignto= value;
+        } else {
+          if (*p == '=') badusage("-%c option does not take a value",cip->oshort);
+          if (cip->call) cip->call(cip,0);
+          else *cip->iassignto= cip->arg;
+        }
+      }
+    }
+  }
+}