Add /.args feature to Redbean/Lua/SQLite/Python/QuickJS

You now have some ability to truly make an executable yours, by adding a
`.args` file to the root of the zip structure. If this is specified,
then you'll be overriding the default CLI args.

This will be a great feature for folks who want to distribute their own
apps, using the interpreter executable, but have the executable appears
to be just your app rather than being the interpreter.

test/tool/args/args_test.c

@@ -0,0 +1,101 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/testlib/testlib.h"
+#include "tool/args/args.h"
+
+void FreeZipArgs(void);
+int LoadZipArgsImpl(int *, char ***, char *);
+
+void TearDown(void) {
+  FreeZipArgs();
+}
+
+TEST(LoadZipArgs, testNoFile_noCliArgs_doesNothing) {
+  int argc = 1;
+  char *args[] = {"prog", 0};
+  char **argv = &args[0];
+  EXPECT_EQ(0, LoadZipArgsImpl(&argc, &argv, 0));
+  ASSERT_EQ(1, argc);
+  EXPECT_STREQ("prog", argv[0]);
+  EXPECT_EQ(NULL, argv[1]);
+}
+
+TEST(LoadZipArgs, testDefaultArgs_noCliArgs_replacesArgv) {
+  int argc = 1;
+  char *args[] = {"prog", 0};
+  char **argv = &args[0];
+  EXPECT_EQ(0, LoadZipArgsImpl(&argc, &argv, strdup("\
+-x\r\n\
+hello\r\n\
+-y\r\n\
+world\r\n\
+")));
+  ASSERT_EQ(5, argc);
+  EXPECT_STREQ("prog", argv[0]);
+  EXPECT_STREQ("-x", argv[1]);
+  EXPECT_STREQ("hello", argv[2]);
+  EXPECT_STREQ("-y", argv[3]);
+  EXPECT_STREQ("world", argv[4]);
+  EXPECT_EQ(NULL, argv[5]);
+  EXPECT_EQ(5, __argc);
+  EXPECT_STREQ("prog", __argv[0]);
+  EXPECT_STREQ("-x", __argv[1]);
+  EXPECT_STREQ("hello", __argv[2]);
+  EXPECT_STREQ("-y", __argv[3]);
+  EXPECT_STREQ("world", __argv[4]);
+  EXPECT_EQ(NULL, __argv[5]);
+}
+
+TEST(LoadZipArgs, testDefaultArgs_hasCliArgs_doesNothing) {
+  int argc = 2;
+  char *args[] = {"prog", "yo", 0};
+  char **argv = &args[0];
+  EXPECT_EQ(0, LoadZipArgsImpl(&argc, &argv, strdup("\
+-x\r\n\
+hello\r\n\
+-y\r\n\
+world\r\n\
+")));
+  ASSERT_EQ(2, argc);
+  EXPECT_STREQ("prog", argv[0]);
+  EXPECT_STREQ("yo", argv[1]);
+  EXPECT_EQ(NULL, argv[2]);
+}
+
+TEST(LoadZipArgs, testDots_hasCliArgs_mergesThem) {
+  int argc = 3;
+  char *args[] = {"prog", "yo", "dawg", 0};
+  char **argv = &args[0];
+  EXPECT_EQ(0, LoadZipArgsImpl(&argc, &argv, strdup("\
+-x\r\n\
+hell o\r\n\
+-y\r\n\
+world\r\n\
+...\r\n\
+")));
+  ASSERT_EQ(7, argc);
+  EXPECT_STREQ("prog", argv[0]);
+  EXPECT_STREQ("-x", argv[1]);
+  EXPECT_STREQ("hell o", argv[2]);
+  EXPECT_STREQ("-y", argv[3]);
+  EXPECT_STREQ("world", argv[4]);
+  EXPECT_STREQ("yo", argv[5]);
+  EXPECT_STREQ("dawg", argv[6]);
+  EXPECT_EQ(NULL, argv[7]);
+}