Handle process arguments

ulib/_premain.c

@@ -1,5 +1,10 @@
 #include <stdint.h>
 #include <stddef.h>
+#include <system/system.h>
+#include <sysdefs/processctl.h>
+#include <errors.h>
+#include <dlmalloc/malloc.h>
+#include <uprintf.h>
 
 extern void main(void);
 
@@ -14,9 +19,36 @@ void bss_clear(void) {
   }
 }
 
+static char **_args;
+static size_t _argslen;
+
+char **args(void) {
+  return _args;
+}
+
+size_t argslen(void) {
+  return _argslen;
+}
+
 // ulib initialization goes here
 void _premain(void) {
   bss_clear();
+
+  _argslen = processctl(-1, PCTL_ARGLEN, 0, 0, 0);
+  _args = dlmalloc(_argslen * sizeof(*_args));
+  if (_args == NULL) {
+    return;
+  }
+  for (size_t i = 0; i < _argslen; i++) {
+    _args[i] = dlmalloc(PROC_ARG_MAX);
+    if (_args[i] == NULL) {
+      return;
+    }
+  }
+  if (processctl(-1, PCTL_ARGV, (uint64_t)_args, _argslen, 0) != E_OK) {
+    return;
+  }
+
   main();
 }