bug: second touch in main.c segfault

core/file.c

@@ -7,14 +7,23 @@
 #include <sys/stat.h>
 #include <sys/types.h>
 
+bool
+contains_percent (const char *s)
+{
+  while (*s)
+    {
+      if (*s == '%')
+        return true;
+      s++;
+    }
+  return false;
+}
+
 error_t
 touch (char *path, char *format, ...)
 {
   error_t err = { 0 };
-  err.null = true; // success by default
+  err.null = true;
-
-  va_list args;
-  va_start (args, format);
 
   FILE *fp = fopen (path, "w");
   if (!fp)
@@ -22,14 +31,22 @@ touch (char *path, char *format, ...)
       err.null = false;
       err.status = errno;
       err.src = strerror (errno);
-      va_end (args);
       return err;
     }
 
+  if (contains_percent (format))
+    {
+      va_list args;
+      va_start (args, format);
       vfprintf (fp, format, args);
-  fclose (fp);
-
       va_end (args);
+    }
+  else
+    {
+      fputs (format, fp);
+    }
+
+  fclose (fp);
   return err;
 }
 

yait/main.c

@@ -1,6 +1,7 @@
 #include "../core/file.h"
 #include "../core/print.h"
 #include "format.h"
+#include <stdio.h>
 
 int create (format_t);
 
@@ -37,6 +38,64 @@ create (format_t fmt)
          "proident, sunt in\n"
          "culpa qui officia deserunt mollit anim id est laborum.",
          fmt.name);
-  touch ("hello", "world");
+  touch ("configure",
+         "#!/bin/sh\n"
+         "\n"
+         "usage() {\n"
+         "cat <<EOF\n"
+         "Usage: $0 [OPTION]... [VAR=VALUE]...\n"
+         "\n"
+         "To assign environment variables (e.g., CC, CFLAGS...), specify them "
+         "as\n"
+         "VAR=VALUE.\n"
+         "\n"
+         "  CC      C compiler command [detected]\n"
+         "  CFLAGS  C compiler flags [-g, ...]\n"
+         "\n"
+         "EOF\n"
+         "exit 0\n"
+         "}\n"
+         "\n"
+         "echo () { printf \"%s\\n\" \"$*\" ; }\n"
+         "cmdexists () { type \"$1\" >/dev/null 2>&1 ; }\n"
+         "trycc () { test -z \"$CC\" && cmdexists \"$1\" && CC=$1 ; }\n"
+         "\n"
+         "prefix=/usr/bin/\n"
+         "CFLAGS=\"-Wall -Wextra -O2\"\n"
+         "LDFLAGS=\n"
+         "CC=\n"
+         "\n"
+         "for arg ; do\n"
+         "case \"$arg\" in\n"
+         "--help|h) usage ;;\n"
+         "CFLAGS=*) CFLAGS=${arg#*=} ;;\n"
+         "LDFLAGS=*) LDFLAGS=${arg#*=} ;;\n"
+         "esac\n"
+         "done\n"
+         "\n"
+         "printf \"checking for C compiler... \"\n"
+         "trycc gcc\n"
+         "trycc cc\n"
+         "trycc clang\n"
+         "printf \"%s\\n\" \"$CC\"\n"
+         "\n"
+         "printf \"checking weather C compiler works... \"\n"
+         "status=\"fail\"\n"
+         "tmpc=\"$(mktemp -d)/test.c\"\n"
+         "echo \"typedef int x;\" > \"$tmpc\"\n"
+         "if output=$($CC $CFLAGS -c -o /dev/null \"$tmpc\" 2>&1) ; then\n"
+         "printf \"yes\\n\"\n"
+         "else\n"
+         "printf \"no; %s\\n\" \"$output\"\n"
+         "exit 1\n"
+         "fi\n"
+         "\n"
+         "printf \"creating config.mak... \"\n"
+         "printf \"PREFIX=%s\\n\" \"$prefix\" > config.mak\n"
+         "printf \"CFLAGS=%s\\n\" \"$CFLAGS\" >> config.mak\n"
+         "printf \"LDFLAGS=%s\\n\" \"$LDFLAGS\" >> config.mak\n"
+         "printf \"CC=%s\\n\" \"$CC\" >> config.mak\n"
+         "printf \"done\\n\"\n",
+         NULL);
   return 0;
 }