1 files changed, 36 insertions, 2 deletions

diff --git a/main.c b/main.c
index 6dcd6ea..edea3de 100644
--- a/main.c
+++ b/main.c
@@ -1,3 +1,4 @@
+#include "common.h"
 #include "parse.h"
 #include <stdlib.h>
 
@@ -10,18 +11,51 @@ flushstd(void)
     ioflush(&bstderr);
 }
 
+static const char *
+optval(const char *arg, const char *opt)
+{
+    /* arg="foo=bar123"; opt="foo"; returns "bar123" */
+    uint n1 = strlen(arg), n2 = strlen(opt);
+    if (n1 < n2+1 || memcmp(arg, opt, n2) != 0 || arg[n2] != '=')
+        return NULL;
+    return arg + n2 + 1;
+}
+
+static void
+optparse(const char **file, const char **targ, char **args)
+{
+    const char *arg, *x;
+    *file = *targ = NULL;
+    while ((arg = *++args)) {
+        if (*arg++ != '-') {
+            *file = arg-1;
+            continue;
+        }
+        if ((x = optval(arg, "std"))) {
+            if (!strcmp(x, "c89")) ccopt.cstd = STDC89;
+            else if (!strcmp(x, "c99")) ccopt.cstd = STDC99;
+            else if (!strcmp(x, "c11")) ccopt.cstd = STDC11;
+            else if (!strcmp(x, "c2x")) ccopt.cstd = STDC23;
+            else if (!strcmp(x, "c23")) ccopt.cstd = STDC23;
+            else goto Bad;
+        } else Bad: warn(NULL, "invalid option: %'s", arg-1);
+    }
+}
+
 int
 main(int argc, char **argv)
 {
     struct parser pr;
+    const char *file, *targ;
 
     atexit(flushstd);
     if (argc < 2) {
         efmt("usage: %s [options] <file>\n", *argv);
         return 1;
     }
+    optparse(&file, &targ, argv);
 
-    targ_init("amd64-sysv");
-    initparser(&pr, argv[1]);
+    targ_init(targ ? targ : "amd64-sysv");
+    initparser(&pr, file);
     parse(&pr);
 }