rename ring_buffer to ringbuffer and remove previous attempt

1 files changed, 0 insertions, 181 deletions

diff --git a/lf_ring_buffer2.c b/lf_ring_buffer2.c
deleted file mode 100644
index 4a1a3cd..0000000
--- a/lf_ring_buffer2.c
+++ /dev/null
@@ -1,181 +0,0 @@
-/*
- * File     : lf_ring_buffer.c
- * Author   : Jérémy Zurcher  <jeremy@asynk.ch>
- * Date     : 05/01/010
- * License  :
- *
- *  Permission is hereby granted, free of charge, to any person obtaining
- *  a copy of this software and associated documentation files (the
- *  "Software"), to deal in the Software without restriction, including
- *  without limitation the rights to use, copy, modify, merge, publish,
- *  distribute, sublicense, and/or sell copies of the Software, and to
- *  permit persons to whom the Software is furnished to do so, subject to
- *  the following conditions:
- *  
- *  The above copyright notice and this permission notice shall be
- *  included in all copies or substantial portions of the Software.
- *  
- *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
- *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
- *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
- *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- *
- */
-
-#include "lf_ring_buffer2.h"
-#include "lf_portable_cas.h"
-#include <stdlib.h>
-#include <string.h>
-#include <time.h>
-
-//#define DEBUG_LFRB_KO 1
-//#define DEBUG_LFRB_CAS 1
-//#define DEBUG_LFRB 1
-
-#ifdef DEBUG_LFRB
-    #include <stdio.h>
-    #define _LOG_KO_( ... ) fprintf(stdout,__VA_ARGS__)
-    #define _LOG_CAS_( ... )fprintf(stdout,__VA_ARGS__)
-#elif defined DEBUG_LFRB_CAS
-    #include <stdio.h>
-    #define _LOG_KO_( ... )
-    #define _LOG_CAS_( ... )fprintf(stdout,__VA_ARGS__)
-#elif defined DEBUG_LFRB_KO
-    #include <stdio.h>
-    #define _LOG_KO_( ... ) fprintf(stdout,__VA_ARGS__)
-    #define _LOG_CAS_( ... )
-#else
-    #define _LOG_KO_( ... )
-    #define _LOG_CAS_( ... )
-#endif
-
-#define BACKOFF_NANO_SLEEP  10
-
-#define USHORTMAX 0xffff
-
-/* An unsigned int (indexes) is used to store both read_from and write_to indexes
- * so that 32 bits compare and swap may be used to update both in one atomic instruction call.
- * To be able to differenciate an empty buffer from a full buffer,
- * read_from part of indexes is set to 0xffff (USHORTMAX) when the buffer is empty.
- * Thus the maximum size of the buffer is 0xffff-1 = 65534 elements
- */
-
-/* initialize an empty lf_ring_buffer struct */
-lf_ring_buffer_t* lf_ring_buffer_create( size_t n_buf ) {
-    if(n_buf>=USHORTMAX) {
-        return NULL;
-    }
-    /* alloc ring_buffer struct */
-    lf_ring_buffer_t *r = malloc(sizeof(lf_ring_buffer_t));
-    if(r==NULL) return NULL;
-    /* alloc buffer */
-    r->buffer = malloc(LFRB_BUFFER_SIZE*n_buf);
-    if(r->buffer==NULL) {
-        free(r);
-        return NULL;
-    }
-    memset(r->buffer,0,LFRB_BUFFER_SIZE*n_buf);
-    r->n_buf = n_buf;
-    r->indexes = (unsigned int)(USHORTMAX<<16) | (unsigned int)0;
-    return r;
-}
-
-/* destroy an lf_ring_buffer strcture */
-void lf_ring_buffer_destroy( lf_ring_buffer_t *r ) {
-    free(r->buffer);
-    free(r);
-}
-
-/* return 1 if is empty */
-int lf_ring_buffer_empty( lf_ring_buffer_t *r ) { return (r->indexes>>16)==USHORTMAX; }
-
-/* write data into the ring buffer */
-int lf_ring_buffer_write( lf_ring_buffer_t *r, void *data, int flags ) {
-    unsigned int current, next;
-    unsigned int write_to, read_from;
-    struct timespec backoff;
-    int backoff_time = BACKOFF_NANO_SLEEP;
-    /* reserve a buffer */
-    for(;;){
-        /* copy indexes and split it */
-        current = r->indexes;
-        write_to = current&0xffff;
-        read_from = current>>16;
-        /*
-         * check if the buffer is available,
-         * if read_from==write_to the buffer is full
-         * if it is available and full, it means that a writer thread which reserved this buffer
-         * hadn't had enough CPU cycles to call MARK_AS_FILLED
-         */
-        if( LFRB_IS_AVAILABLE( r->buffer[write_to] ) && read_from!=write_to ) {
-            next = write_to+1;
-            if (next==r->n_buf) next=0;
-            /* set read_from to write_to if needed */
-            if (read_from==USHORTMAX) {
-                next |= write_to<<16;
-            } else {
-                next |= read_from<<16;
-            }
-            /* try to update indexes */
-            _LOG_CAS_( "write: CAS %u %u %u\n", r->indexes, current, next );
-            if( CompareAndSwapInt( &r->indexes, current, next ) ) break;
-        } else {
-            _LOG_KO_("write: impossible : wt:%d rf:%d wa:%d\n",write_to,read_from,LFRB_IS_AVAILABLE(r->buffer[write_to]));
-            if(IS_NOT_BLOCKING(flags)) return -1;
-        }
-        /* sleep */
-        backoff.tv_sec = 0;
-        backoff.tv_nsec = backoff_time;
-        nanosleep(&backoff,NULL);
-        backoff_time += BACKOFF_NANO_SLEEP;
-    }
-    /* fill this buffer and mark it as filled */
-    memcpy( LFRB_DATA_PTR(r->buffer[write_to]), data, LFRB_DATA_SIZE );
-    LFRB_MARK_AS_FILLED( r->buffer[write_to] );
-    return 0;
-}
-
-/* read data from the ring buffer */
-int lf_ring_buffer_read( lf_ring_buffer_t *r, void *data, int flags ) {
-    unsigned int current, next;
-    unsigned int write_to, read_from, tmp;
-    struct timespec backoff;
-    int backoff_time = BACKOFF_NANO_SLEEP;
-    for(;;) {
-        /* copy indexes and split it */
-        current = r->indexes;
-        write_to = current&0xffff;
-        read_from = current>>16;
-        /*
-         * the buffer may be non empty but available if a writer thread hadn't had enough CPU cycles to mark the buffer as filled
-         */
-        if( read_from==USHORTMAX || LFRB_IS_AVAILABLE( r->buffer[read_from] ) ) {
-            _LOG_KO_("read : impossible : wt:%d rf:%d ra:%d\n",write_to,read_from,LFRB_IS_AVAILABLE(r->buffer[read_from]));
-            if(IS_NOT_BLOCKING(flags)) return -1;
-        } else {
-            tmp = read_from +1;
-            if (tmp==r->n_buf) tmp=0;
-            /* set the buffer empty if needed */
-            if (tmp==write_to) {
-                tmp = USHORTMAX;
-            }
-            next = tmp<<16 | write_to;
-            /* try to update indexes */
-            _LOG_CAS_( "read: CAS %u %u %u\n", r->indexes, current, next );
-            if( CompareAndSwapInt( &r->indexes, current , next ) ) break;
-        }
-        /* sleep */
-        backoff.tv_sec = 0;
-        backoff.tv_nsec = backoff_time;
-        nanosleep(&backoff,NULL);
-        backoff_time += BACKOFF_NANO_SLEEP;
-    }
-    /* copy this buffer and mark it as read */
-    memcpy( data, LFRB_DATA_PTR(r->buffer[read_from]), LFRB_DATA_SIZE );
-    LFRB_MARK_AS_READ( r->buffer[read_from] );
-    return 0;
-}
-