ogl_beamforming

os_linux.c (7032B)

---

 /* See LICENSE for license details. */
 
 /* NOTE(rnp): provides the platform layer for the beamformer. This code must
  * be provided by any platform the beamformer is ported to. */
 
 #define OS_SHARED_MEMORY_NAME "/ogl_beamformer_shared_memory"
 
 #define OS_PATH_SEPARATOR_CHAR '/'
 #define OS_PATH_SEPARATOR      "/"
 
 #include "util.h"
 
 #include <dlfcn.h>
 #include <fcntl.h>
 #include <linux/futex.h>
 #include <poll.h>
 #include <pthread.h>
 #include <sys/inotify.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <sys/syscall.h>
 #include <unistd.h>
 
 /* NOTE(rnp): hidden behind feature flags -> screw compiler/standards idiots */
 #ifndef CLOCK_MONOTONIC
   #define CLOCK_MONOTONIC 1
 #endif
 i32 ftruncate(i32, i64);
 i64 syscall(i64, ...);
 i32 clock_gettime(i32, struct timespec *);
 
 #ifdef _DEBUG
 function void *
 os_get_module(char *name, Stream *e)
 {
 	void *result = dlopen(name, RTLD_NOW|RTLD_LOCAL|RTLD_NOLOAD);
 	if (!result && e) {
 		stream_append_s8s(e, s8("os_get_module(\""), c_str_to_s8(name), s8("\"): "),
 		                  c_str_to_s8(dlerror()), s8("\n"));
 	}
 	return result;
 }
 #endif
 
 function OS_WRITE_FILE_FN(os_write_file)
 {
 	while (raw.len) {
 		iz r = write(file, raw.data, raw.len);
 		if (r < 0) return 0;
 		raw = s8_cut_head(raw, r);
 	}
 	return 1;
 }
 
 function void __attribute__((noreturn))
 os_exit(i32 code)
 {
 	_exit(code);
 	unreachable();
 }
 
 function void __attribute__((noreturn))
 os_fatal(s8 msg)
 {
 	os_write_file(STDERR_FILENO, msg);
 	os_exit(1);
 	unreachable();
 }
 
 function u64
 os_get_timer_frequency(void)
 {
 	return 1000000000ULL;
 }
 
 function u64
 os_get_timer_counter(void)
 {
 	struct timespec time = {0};
 	clock_gettime(CLOCK_MONOTONIC, &time);
 	u64 result = time.tv_sec * 1000000000ULL + time.tv_nsec;
 	return result;
 }
 
 function iz
 os_round_up_to_page_size(iz value)
 {
 	iz result = round_up_to(value, sysconf(_SC_PAGESIZE));
 	return result;
 }
 
 function OS_ALLOC_ARENA_FN(os_alloc_arena)
 {
 	Arena result = {0};
 	capacity   = os_round_up_to_page_size(capacity);
 	result.beg = mmap(0, capacity, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
 	if (result.beg == MAP_FAILED)
 		os_fatal(s8("os_alloc_arena: couldn't allocate memory\n"));
 	result.end = result.beg + capacity;
 	return result;
 }
 
 function OS_READ_WHOLE_FILE_FN(os_read_whole_file)
 {
 	s8 result = s8("");
 
 	struct stat sb;
 	i32 fd = open(file, O_RDONLY);
 	if (fd >= 0 && fstat(fd, &sb) >= 0) {
 		result = s8_alloc(arena, sb.st_size);
 		iz rlen = read(fd, result.data, result.len);
 		if (rlen != result.len)
 			result = s8("");
 	}
 	if (fd >= 0) close(fd);
 
 	return result;
 }
 
 function OS_WRITE_NEW_FILE_FN(os_write_new_file)
 {
 	iptr fd = open(fname, O_WRONLY|O_TRUNC|O_CREAT, 0600);
 	if (fd == INVALID_FILE)
 		return 0;
 	b32 ret = os_write_file(fd, raw);
 	close(fd);
 	return ret;
 }
 
 function b32
 os_file_exists(char *path)
 {
 	struct stat st;
 	b32 result = stat(path, &st) == 0;
 	return result;
 }
 
 function SharedMemoryRegion
 os_create_shared_memory_area(Arena *arena, char *name, i32 lock_count, iz requested_capacity)
 {
 	iz capacity = os_round_up_to_page_size(requested_capacity);
 	SharedMemoryRegion result = {0};
 	i32 fd = shm_open(name, O_CREAT|O_RDWR, S_IRUSR|S_IWUSR);
 	if (fd > 0 && ftruncate(fd, capacity) != -1) {
 		void *new = mmap(0, capacity, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
 		if (new != MAP_FAILED) result.region = new;
 	}
 	if (fd > 0) close(fd);
 	return result;
 }
 
 /* NOTE: complete garbage because there is no standarized copyfile() in POSix */
 function b32
 os_copy_file(char *name, char *new)
 {
 	b32 result = 0;
 	struct stat sb;
 	if (stat(name, &sb) == 0) {
 		i32 fd_old = open(name, O_RDONLY);
 		i32 fd_new = open(new,  O_WRONLY|O_CREAT, sb.st_mode);
 		if (fd_old >= 0 && fd_new >= 0) {
 			u8 buf[4096];
 			iz copied = 0;
 			while (copied != sb.st_size) {
 				iz r = read(fd_old, buf, countof(buf));
 				if (r < 0) break;
 				iz w = write(fd_new, buf, r);
 				if (w < 0) break;
 				copied += w;
 			}
 			result = copied == sb.st_size;
 		}
 		if (fd_old != -1) close(fd_old);
 		if (fd_new != -1) close(fd_new);
 	}
 	return result;
 }
 
 function void *
 os_load_library(char *name, char *temp_name, Stream *e)
 {
 	if (temp_name) {
 		if (os_copy_file(name, temp_name))
 			name = temp_name;
 	}
 
 	void *result = dlopen(name, RTLD_NOW|RTLD_LOCAL);
 	if (!result && e) {
 		stream_append_s8s(e, s8("os_load_library(\""), c_str_to_s8(name), s8("\"): "),
 		                  c_str_to_s8(dlerror()), s8("\n"));
 	}
 
 	if (temp_name)
 		unlink(temp_name);
 
 	return result;
 }
 
 function void *
 os_lookup_dynamic_symbol(void *h, char *name, Stream *e)
 {
 	void *result = 0;
 	if (h) {
 		result = dlsym(h, name);
 		if (!result && e) {
 			stream_append_s8s(e, s8("os_lookup_dynamic_symbol(\""), c_str_to_s8(name),
 			                  s8("\"): "), c_str_to_s8(dlerror()), s8("\n"));
 		}
 	}
 	return result;
 }
 
 function void
 os_unload_library(void *h)
 {
 	/* NOTE: glibc is buggy gnuware so we need to check this */
 	if (h)
 		dlclose(h);
 }
 
 function OS_ADD_FILE_WATCH_FN(os_add_file_watch)
 {
 	s8 directory  = path;
 	directory.len = s8_scan_backwards(path, '/');
 	ASSERT(directory.len > 0);
 
 	u64 hash = s8_hash(directory);
 	FileWatchContext *fwctx = &os->file_watch_context;
 	FileWatchDirectory *dir = lookup_file_watch_directory(fwctx, hash);
 	if (!dir) {
 		ASSERT(path.data[directory.len] == '/');
 		dir = da_push(a, fwctx);
 		dir->hash   = hash;
 		dir->name   = push_s8_zero(a, directory);
 		i32 mask    = IN_MOVED_TO|IN_CLOSE_WRITE;
 		dir->handle = inotify_add_watch(fwctx->handle, (c8 *)dir->name.data, mask);
 	}
 
 	FileWatch *fw = da_push(a, dir);
 	fw->user_data = user_data;
 	fw->callback  = callback;
 	fw->hash      = s8_hash(s8_cut_head(path, dir->name.len + 1));
 }
 
 i32 pthread_setname_np(pthread_t, char *);
 function iptr
 os_create_thread(Arena arena, iptr user_context, s8 name, os_thread_entry_point_fn *fn)
 {
 	pthread_t result;
 	pthread_create(&result, 0, (void *(*)(void *))fn, (void *)user_context);
 	pthread_setname_np(result, (char *)name.data);
 	return (iptr)result;
 }
 
 function OS_WAIT_ON_VALUE_FN(os_wait_on_value)
 {
 	struct timespec *timeout = 0, timeout_value;
 	if (timeout_ms != (u32)-1) {
 		timeout_value.tv_sec  = timeout_ms / 1000;
 		timeout_value.tv_nsec = (timeout_ms % 1000) * 1000000;
 		timeout = &timeout_value;
 	}
 	return syscall(SYS_futex, value, FUTEX_WAIT, current, timeout, 0, 0) == 0;
 }
 
 function OS_WAKE_WAITERS_FN(os_wake_waiters)
 {
 	if (sync) {
 		atomic_store_u32(sync, 0);
 		syscall(SYS_futex, sync, FUTEX_WAKE, I32_MAX, 0, 0, 0);
 	}
 }
 
 function OS_SHARED_MEMORY_LOCK_REGION_FN(os_shared_memory_region_lock)
 {
 	b32 result = 0;
 	for (;;) {
 		i32 current = atomic_load_u32(locks + lock_index);
 		if (current == 0 && atomic_cas_u32(locks + lock_index, &current, 1)) {
 			result = 1;
 			break;
 		}
 		if (!timeout_ms || !os_wait_on_value(locks + lock_index, current, timeout_ms))
 			break;
 	}
 	return result;
 }
 
 function OS_SHARED_MEMORY_UNLOCK_REGION_FN(os_shared_memory_region_unlock)
 {
 	i32 *lock = locks + lock_index;
 	assert(atomic_load_u32(lock));
 	atomic_store_u32(lock, 0);
 	os_wake_waiters(lock);
 }