Initial public snapshot

With code from Bill. Thanks Bill!

1 files changed, 145 insertions, 0 deletions

diff --git a/src/os.h b/src/os.h
new file mode 100644
index 0000000..c74d2d0
--- /dev/null
+++ b/src/os.h
@@ -0,0 +1,145 @@
+/*
+ * Copyright © 2021 Michael Smith <mikesmiffy128@gmail.com>
+ *
+ * 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.
+ */
+
+#ifndef INC_OS_H
+#define INC_OS_H
+
+#include <stdbool.h>
+
+/*
+ * Here we declare an absolute ton of wrappers, macros, compatibility shims,
+ * reimplementations and so on to try in vain to sweep the inconsistencies
+ * between Windows and not-Windows under the rug.
+ *
+ * If this file gets any bigger it might need to be split up a bit...
+ */
+
+#include <fcntl.h>
+#ifdef _WIN32
+#define NOMINMAX
+#define WIN32_LEAN_AND_MEAN
+#include <io.h>
+#include <wchar.h>
+#include <Windows.h>
+#else
+#include <dlfcn.h>
+#include <limits.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#endif
+
+#include "intdefs.h"
+
+#ifdef _WIN32
+
+#define IMPORT __declspec(dllimport) // only needed for variables
+#define EXPORT __declspec(dllexport)
+void *os_dlsym(void *mod, const char *sym);
+#define os_char ushort
+#define _OS_CAT(L, x) L##x
+#define OS_LIT(x) _OS_CAT(L, x)
+#define os_snprintf _snwprintf
+#define os_strchr wcschr
+#define os_strcmp wcscmp
+#define os_strcpy wcscpy
+#define os_strlen wcslen
+#define strncasecmp _strnicmp // stupid!
+#define OS_DLSUFFIX ".dll"
+#ifndef PATH_MAX
+// XXX win32/crt has this dumb 260 limit even though the actual kernel imposes
+// no limit (though apparently NTFS has a limit of 65535). Theoerically we could
+// do some memes with UNC paths to extend it to at least have parity with Unix
+// PATH_MAX (4096), but for now we just kind of accept that Windows is a
+// disaster.
+#define PATH_MAX MAX_PATH
+#endif
+#define os_fopen _wfopen
+// yuck :(
+#define _os_open3(path, flags, mode) _wopen((path), (flags) | _O_BINARY, (mode))
+#define _os_open2(path, flags) _wopen((path), (flags) | _O_BINARY)
+#define _os_open(a, b, c, x, ...) x
+#define os_open(...) _os_open(__VA_ARGS__, _os_open3, _os_open2, _)(__VA_ARGS__)
+#define os_access _waccess
+#define os_stat _stat64
+// ucrt defines __stat64 to _stat64. we want _wstat64 to be the actual function
+#define _stat64(path, buf) _wstat64(path, buf)
+// why exactly _does_ windows prefix so many things with underscores?
+#define read _read
+#define write _write
+#define close _close
+#define O_RDONLY _O_RDONLY
+#define O_RDWR _O_RDWR
+#define O_CLOEXEC _O_NOINHERIT
+#define O_CREAT _O_CREAT
+#define O_EXCL _O_EXCL
+#define F_OK 0
+#define R_OK 4
+#define W_OK 2
+#define X_OK R_OK // there's no actual X bit
+#define alloca _alloca
+#define os_getenv _wgetenv
+#define OS_MAIN wmain
+// just dump this boilerplate here as well, I spose
+#define OS_WINDOWS_ERROR(arrayname) \
+	FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM, 0, GetLastError(), \
+			MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), arrayname, \
+			sizeof(arrayname), 0)
+
+#else
+
+#ifdef __GNUC__
+#define EXPORT __attribute__((visibility("default")))
+#else
+#define EXPORT int novis[-!!"visibility attribute requires Clang or GCC"];
+#endif
+#define IMPORT
+#define os_dlsym dlsym
+#define os_char char
+#define OS_LIT(x) x
+#define os_snprintf snprintf
+#define os_strchr strchr
+#define os_strcmp strcmp
+#define os_strcpy strcpy
+#define os_strlen strlen
+#define OS_DLSUFFIX ".so"
+#define os_fopen fopen
+#define os_open open
+#define os_access access
+#define os_stat stat
+// unix mprot flags are much nicer but cannot be defined in terms of the windows
+// ones, so we use the windows ones and define them in terms of the unix ones.
+// another victory for stupid!
+#define PAGE_NOACCESS			0
+#define PAGE_READONLY			PROT_READ
+#define PAGE_READWRITE			PROT_READ | PROT_WRITE
+#define PAGE_EXECUTE_READ		PROT_READ |              PROT_EXEC
+#define PAGE_EXECUTE_READWRITE	PROT_READ | PROT_WRITE | PROT_EXEC
+#define os_getenv getenv
+#define OS_MAIN main
+
+#endif
+
+bool os_mprot(void *addr, int len, int fl);
+/*
+ * NOTE: this should be called with a reasonably small buffer (e.g., the size of
+ * a private key). The maximum size of the buffer on Linux is 256, on Windows
+ * it's God Knows What.
+ */
+void os_randombytes(void *buf, int len);
+
+#endif
+
+// vi: sw=4 ts=4 noet tw=80 cc=80