diff options
Diffstat (limited to 'zix')
| -rw-r--r-- | zix/common.h | 83 | ||||
| -rw-r--r-- | zix/ring.c | 225 | ||||
| -rw-r--r-- | zix/ring.h | 130 | ||||
| -rw-r--r-- | zix/thread.h | 133 |
4 files changed, 571 insertions, 0 deletions
diff --git a/zix/common.h b/zix/common.h new file mode 100644 index 0000000..59e1f55 --- /dev/null +++ b/zix/common.h @@ -0,0 +1,83 @@ +/* + Copyright 2011 David Robillard <http://drobilla.net> + + 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. + + THIS 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 ZIX_COMMON_H +#define ZIX_COMMON_H + +/** + @addtogroup zix + @{ +*/ + +/** @cond */ +#ifdef ZIX_SHARED +# ifdef _WIN32 +# define ZIX_LIB_IMPORT __declspec(dllimport) +# define ZIX_LIB_EXPORT __declspec(dllexport) +# else +# define ZIX_LIB_IMPORT __attribute__((visibility("default"))) +# define ZIX_LIB_EXPORT __attribute__((visibility("default"))) +# endif +# ifdef ZIX_INTERNAL +# define ZIX_API ZIX_LIB_EXPORT +# else +# define ZIX_API ZIX_LIB_IMPORT +# endif +#else +# define ZIX_API +#endif +/** @endcond */ + +#ifdef __cplusplus +extern "C" { +#else +# include <stdbool.h> +#endif + +typedef enum { + ZIX_STATUS_SUCCESS, + ZIX_STATUS_ERROR, + ZIX_STATUS_NO_MEM, + ZIX_STATUS_NOT_FOUND, + ZIX_STATUS_EXISTS, + ZIX_STATUS_BAD_ARG, + ZIX_STATUS_BAD_PERMS, +} ZixStatus; + +/** + Function for comparing two elements. +*/ +typedef int (*ZixComparator)(const void* a, const void* b, void* user_data); + +/** + Function for testing equality of two elements. +*/ +typedef bool (*ZixEqualFunc)(const void* a, const void* b); + +/** + Function to destroy an element. +*/ +typedef void (*ZixDestroyFunc)(void* ptr); + +/** + @} +*/ + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* ZIX_COMMON_H */ diff --git a/zix/ring.c b/zix/ring.c new file mode 100644 index 0000000..7ebbe67 --- /dev/null +++ b/zix/ring.c @@ -0,0 +1,225 @@ +/* + Copyright 2011 David Robillard <http://drobilla.net> + + 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. + + THIS 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 <stdint.h> +#include <stdlib.h> +#include <string.h> + +#ifdef HAVE_MLOCK +# include <sys/mman.h> +# define ZIX_MLOCK(ptr, size) mlock((ptr), (size)) +#elif defined(_WIN32) +# include <windows.h> +# define ZIX_MLOCK(ptr, size) VirtualLock((ptr), (size)) +#else +# pragma message("warning: No memory locking, possible RT violations") +# define ZIX_MLOCK(ptr, size) +#endif + +#if defined(__APPLE__) +# include <libkern/OSAtomic.h> +# define ZIX_FULL_BARRIER() OSMemoryBarrier() +#elif defined(_WIN32) +# include <windows.h> +# define ZIX_FULL_BARRIER() MemoryBarrier() +#elif (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1) +# define ZIX_FULL_BARRIER() __sync_synchronize() +#else +# pragma message("warning: No memory barriers, possible SMP bugs") +# define ZIX_FULL_BARRIER() +#endif + +/* No support for any systems with separate read and write barriers */ +#define ZIX_READ_BARRIER() ZIX_FULL_BARRIER() +#define ZIX_WRITE_BARRIER() ZIX_FULL_BARRIER() + +#include "zix/ring.h" + +struct ZixRingImpl { + uint32_t write_head; ///< Read index into buf + uint32_t read_head; ///< Write index into buf + uint32_t size; ///< Size (capacity) in bytes + uint32_t size_mask; ///< Mask for fast modulo + char* buf; ///< Contents +}; + +static inline uint32_t +next_power_of_two(uint32_t size) +{ + // http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2 + size--; + size |= size >> 1; + size |= size >> 2; + size |= size >> 4; + size |= size >> 8; + size |= size >> 16; + size++; + return size; +} + +ZixRing* +zix_ring_new(uint32_t size) +{ + ZixRing* ring = (ZixRing*)malloc(sizeof(ZixRing)); + ring->write_head = 0; + ring->read_head = 0; + ring->size = next_power_of_two(size); + ring->size_mask = ring->size - 1; + ring->buf = (char*)malloc(ring->size); + return ring; +} + +void +zix_ring_free(ZixRing* ring) +{ + free(ring->buf); + free(ring); +} + +void +zix_ring_mlock(ZixRing* ring) +{ + ZIX_MLOCK(ring, sizeof(ZixRing)); + ZIX_MLOCK(ring->buf, ring->size); +} + +void +zix_ring_reset(ZixRing* ring) +{ + ring->write_head = 0; + ring->read_head = 0; +} + +static inline uint32_t +read_space_internal(const ZixRing* ring, uint32_t r, uint32_t w) +{ + if (r < w) { + return w - r; + } else { + return (w - r + ring->size) & ring->size_mask; + } +} + +uint32_t +zix_ring_read_space(const ZixRing* ring) +{ + return read_space_internal(ring, ring->read_head, ring->write_head); +} + +static inline uint32_t +write_space_internal(const ZixRing* ring, uint32_t r, uint32_t w) +{ + if (r == w) { + return ring->size - 1; + } else if (r < w) { + return ((r - w + ring->size) & ring->size_mask) - 1; + } else { + return (r - w) - 1; + } +} + +uint32_t +zix_ring_write_space(const ZixRing* ring) +{ + return write_space_internal(ring, ring->read_head, ring->write_head); +} + +uint32_t +zix_ring_capacity(const ZixRing* ring) +{ + return ring->size - 1; +} + +static inline uint32_t +peek_internal(const ZixRing* ring, uint32_t r, uint32_t w, + uint32_t size, void* dst) +{ + if (read_space_internal(ring, r, w) < size) { + return 0; + } + + if (r + size < ring->size) { + memcpy(dst, &ring->buf[r], size); + } else { + const uint32_t first_size = ring->size - r; + memcpy(dst, &ring->buf[r], first_size); + memcpy((char*)dst + first_size, &ring->buf[0], size - first_size); + } + + return size; +} + +uint32_t +zix_ring_peek(ZixRing* ring, void* dst, uint32_t size) +{ + const uint32_t r = ring->read_head; + const uint32_t w = ring->write_head; + + return peek_internal(ring, r, w, size, dst); +} + +uint32_t +zix_ring_read(ZixRing* ring, void* dst, uint32_t size) +{ + const uint32_t r = ring->read_head; + const uint32_t w = ring->write_head; + + if (peek_internal(ring, r, w, size, dst)) { + ZIX_READ_BARRIER(); + ring->read_head = (r + size) & ring->size_mask; + return size; + } else { + return 0; + } +} + +uint32_t +zix_ring_skip(ZixRing* ring, uint32_t size) +{ + const uint32_t r = ring->read_head; + const uint32_t w = ring->write_head; + if (read_space_internal(ring, r, w) < size) { + return 0; + } + + ZIX_READ_BARRIER(); + ring->read_head = (r + size) & ring->size_mask; + return size; +} + +uint32_t +zix_ring_write(ZixRing* ring, const void* src, uint32_t size) +{ + const uint32_t r = ring->read_head; + const uint32_t w = ring->write_head; + if (write_space_internal(ring, r, w) < size) { + return 0; + } + + if (w + size <= ring->size) { + memcpy(&ring->buf[w], src, size); + ZIX_WRITE_BARRIER(); + ring->write_head = (w + size) & ring->size_mask; + } else { + const uint32_t this_size = ring->size - w; + memcpy(&ring->buf[w], src, this_size); + memcpy(&ring->buf[0], (char*)src + this_size, size - this_size); + ZIX_WRITE_BARRIER(); + ring->write_head = size - this_size; + } + + return size; +} diff --git a/zix/ring.h b/zix/ring.h new file mode 100644 index 0000000..34ba2fa --- /dev/null +++ b/zix/ring.h @@ -0,0 +1,130 @@ +/* + Copyright 2011 David Robillard <http://drobilla.net> + + 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. + + THIS 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 ZIX_RING_H +#define ZIX_RING_H + +#include <stdint.h> + +#include "zix/common.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/** + @addtogroup zix + @{ + @name Ring + @{ +*/ + +/** + A lock-free ring buffer. + + Thread-safe with a single reader and single writer, and realtime safe + on both ends. +*/ +typedef struct ZixRingImpl ZixRing; + +/** + Create a new ring. + @param size Size in bytes (note this may be rounded up). + + At most @c size - 1 bytes may be stored in the ring at once. +*/ +ZixRing* +zix_ring_new(uint32_t size); + +/** + Destroy a ring. +*/ +void +zix_ring_free(ZixRing* ring); + +/** + Lock the ring data into physical memory. + + This function is NOT thread safe or real-time safe, but it should be called + after zix_ring_new() to lock all ring memory to avoid page faults while + using the ring (i.e. this function MUST be called first in order for the + ring to be truly real-time safe). + +*/ +void +zix_ring_mlock(ZixRing* ring); + +/** + Reset (empty) a ring. + + This function is NOT thread-safe, it may only be called when there are no + readers or writers. +*/ +void +zix_ring_reset(ZixRing* ring); + +/** + Return the number of bytes of space available for reading. +*/ +uint32_t +zix_ring_read_space(const ZixRing* ring); + +/** + Return the number of bytes of space available for writing. +*/ +uint32_t +zix_ring_write_space(const ZixRing* ring); + +/** + Return the capacity (i.e. total write space when empty). +*/ +uint32_t +zix_ring_capacity(const ZixRing* ring); + +/** + Read from the ring without advancing the read head. +*/ +uint32_t +zix_ring_peek(ZixRing* ring, void* dst, uint32_t size); + +/** + Read from the ring and advance the read head. +*/ +uint32_t +zix_ring_read(ZixRing* ring, void* dst, uint32_t size); + +/** + Skip data in the ring (advance read head without reading). +*/ +uint32_t +zix_ring_skip(ZixRing* ring, uint32_t size); + +/** + Write data to the ring. +*/ +uint32_t +zix_ring_write(ZixRing* ring, const void* src, uint32_t size); + +/** + @} + @} +*/ + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* ZIX_RING_H */ diff --git a/zix/thread.h b/zix/thread.h new file mode 100644 index 0000000..ff5a727 --- /dev/null +++ b/zix/thread.h @@ -0,0 +1,133 @@ +/* + Copyright 2012 David Robillard <http://drobilla.net> + + 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. + + THIS 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 ZIX_THREAD_H +#define ZIX_THREAD_H + +#ifdef _WIN32 +# include <windows.h> +#else +# include <errno.h> +# include <pthread.h> +#endif + +#include "zix/common.h" + +#ifdef __cplusplus +extern "C" { +#else +# include <stdbool.h> +#endif + +/** + @addtogroup zix + @{ + @name Thread + @{ +*/ + +#ifdef _WIN32 +typedef HANDLE ZixThread; +#else +typedef pthread_t ZixThread; +#endif + +/** + Initialize @c thread to a new thread. + + The thread will immediately be launched, calling @c function with @c arg + as the only parameter. +*/ +static inline ZixStatus +zix_thread_create(ZixThread* thread, + size_t stack_size, + void* (*function)(void*), + void* arg); + +/** + Join @c thread (block until @c thread exits). +*/ +static inline ZixStatus +zix_thread_join(ZixThread thread, void** retval); + +#ifdef _WIN32 + +static inline ZixStatus +zix_thread_create(ZixThread* thread, + size_t stack_size, + void* (*function)(void*), + void* arg) +{ + *thread = CreateThread(NULL, stack_size, + (LPTHREAD_START_ROUTINE)function, arg, + 0, NULL); + return *thread ? ZIX_STATUS_SUCCESS : ZIX_STATUS_ERROR; +} + +static inline ZixStatus +zix_thread_join(ZixThread thread, void** retval) +{ + return WaitForSingleObject(thread, INFINITE) + ? ZIX_STATUS_SUCCESS : ZIX_STATUS_ERROR; +} + +#else /* !defined(_WIN32) */ + +static inline ZixStatus +zix_thread_create(ZixThread* thread, + size_t stack_size, + void* (*function)(void*), + void* arg) +{ + pthread_attr_t attr; + pthread_attr_init(&attr); + pthread_attr_setstacksize(&attr, stack_size); + + const int ret = pthread_create(thread, NULL, function, arg); + pthread_attr_destroy(&attr); + + if (ret == EAGAIN) { + return ZIX_STATUS_NO_MEM; + } else if (ret == EINVAL) { + return ZIX_STATUS_BAD_ARG; + } else if (ret == EPERM) { + return ZIX_STATUS_BAD_PERMS; + } else if (ret) { + return ZIX_STATUS_ERROR; + } + + return ZIX_STATUS_SUCCESS; +} + +static inline ZixStatus +zix_thread_join(ZixThread thread, void** retval) +{ + return pthread_join(thread, retval) + ? ZIX_STATUS_ERROR : ZIX_STATUS_SUCCESS; +} + +#endif + +/** + @} + @} +*/ + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +#endif /* ZIX_THREAD_H */ |