Rework OS abstractions

- As much as possible avoid dragging system headers into translation
  units. This should avoid namespace pollution and, hopefully, speed up
  builds a little bit.

- Avoid leaning on the UCRT so much on Windows - prefer native win32
  calls and native file handles except where doing so is inconvenient
  (in particular, for stat(), which we might try and replace later).

- Also, switch from SystemFunction036 to ProcessPrng on Windows. This
  requires us to generate a stub for bcryptprimitives.dll because
  Microsoft haven't bothered to provide a link library, but the function
  is better-documented and seems to be a more direct under-the-hood call
  as well. Apparently it's what's used by the major web browsers these
  days, which seems like a good indication it's stable and trusted.

- Lastly, remove a bunch of functions and macros and stuff that weren't
  actually being used. It seems good to try and keep the scope of
  OS-dependent stuff relatively contained and only add to it when
  actually required.

1 files changed, 0 insertions, 125 deletions

diff --git a/src/os-unix.h b/src/os-unix.h
deleted file mode 100644
index 097d300..0000000
--- a/src/os-unix.h
+++ /dev/null
@@ -1,125 +0,0 @@
-/*
- * Copyright © 2023 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.
- */
-
-/* Unix-specific definitions for os.h - don't include this directly! */
-
-#ifdef __GNUC__
-#define EXPORT __attribute__((visibility("default")))
-#else
-#define EXPORT int novis[-!!"visibility attribute requires Clang or GCC"];
-#endif
-#define IMPORT
-
-typedef char os_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_fopen fopen
-#define os_open open
-#define os_access access
-#define os_stat stat
-#define os_mkdir(f) mkdir(f, 0755) // use real mkdir(2) if the mode matters
-#define os_unlink unlink
-#define os_getenv getenv
-#define os_getcwd getcwd
-
-#define OS_DLPREFIX "lib"
-#define OS_DLSUFFIX ".so"
-
-#define OS_MAIN main
-
-static inline void *os_dlopen(const char *name) {
-	return dlopen(name, RTLD_NOW);
-}
-#define os_dlsym dlsym
-
-#ifdef __linux__
-// note: this is glibc-specific. it shouldn't be used in build-time code, just
-// the plugin itself (that really shouldn't be a problem).
-
-// private struct hidden behind _GNU_SOURCE. see dlinfo(3) or <link.h>
-struct gnu_link_map {
-	unsigned long l_addr;
-	const char *l_name;
-	void *l_ld;
-	struct gnu_link_map *l_next, *l_prev;
-	// [more private stuff below]
-};
-
-static inline void *os_dlhandle(const char *name) {
-	extern struct gnu_link_map *_os_lmbase; // note: defined in sst.c for now
-	if (!_os_lmbase) { // IMPORTANT: not thread safe. don't forget later!
-		_os_lmbase = (struct gnu_link_map *)dlopen("libc.so.6",
-				RTLD_LAZY | RTLD_NOLOAD);
-		dlclose(_os_lmbase); // assume success
-		while (_os_lmbase->l_prev) _os_lmbase = _os_lmbase->l_prev;
-	}
-	// this is a tiny bit crude, but basically okay. we just want to find
-	// something that roughly matches the basename, rather than needing an exact
-	// path, in a manner vaguely similar to Windows' GetModuleHandle(). that way
-	// we can just look up client.so or something without having to figure out
-	// where exactly that is.
-	for (struct gnu_link_map *lm = _os_lmbase; lm; lm = lm->l_next) {
-		if (name[0] == '/') {
-			if (!strcmp(name, lm->l_name)) return lm;
-			continue;
-		}
-		int namelen = strlen(lm->l_name);
-		int sublen = strlen(name);
-		if (sublen >= namelen) continue;
-		if (lm->l_name[namelen - sublen - 1] == '/' && !memcmp(
-				lm->l_name + namelen - sublen, name, sublen)) {
-			return lm;
-		}
-	}
-	return 0;
-}
-
-static inline int os_dlfile(void *m, char *buf, int sz) {
-	struct gnu_link_map *lm = m;
-	int ssz = strlen(lm->l_name) + 1;
-	if (ssz > sz) { errno = ENAMETOOLONG; return -1; }
-	memcpy(buf, lm->l_name, ssz);
-	return ssz;
-}
-
-#endif
-
-// 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
-
-static inline bool os_mprot(void *addr, int len, int fl) {
-	// round down address and round up size
-	addr = (void *)((unsigned long)addr & ~(4095));
-	len = len + 4095 & ~(4095);
-	return mprotect(addr, len, fl) != -1;
-}
-
-static inline void os_randombytes(void *buf, int sz) {
-	// if this call fails, the system is doomed, so loop until success and pray.
-	while (getentropy(buf, sz) == -1);
-}
-
-// vi: sw=4 ts=4 noet tw=80 cc=80