ucx/mempool.c

Thu, 21 Dec 2017 19:48:27 +0100

author
Mike Becker <universe@uap-core.de>
date
Thu, 21 Dec 2017 19:48:27 +0100
changeset 359
bacb54502b24
parent 335
c1bc13faadaa
child 505
481802342fdf
permissions
-rw-r--r--

davql: allow ANYWHERE keyword in SELECT statements

This may seem pointless, but users might want to be explicit about this and the grammar is more consistent.

This commit also adds some no-ops to the functions body of the SET parser, because some day the grammar might allow more clauses after the WHERE clause.

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2017 Mike Becker, Olaf Wintermann All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "ucx/mempool.h"

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#ifdef __cplusplus
#define __STDC_FORMAT_MACROS
#endif
#include <inttypes.h>

/** Capsule for destructible memory chunks. */
typedef struct {
    /** The destructor for the memory chunk. */
    ucx_destructor destructor;
    /**
     * First byte of the memory chunk.
     * Note, that the address <code>&amp;c</code> is also the address
     * of the whole memory chunk.
     */
    char c;
} ucx_memchunk;

/** Capsule for data and its destructor. */
typedef struct {
    /** The destructor for the data. */
    ucx_destructor destructor;
    /** A pointer to the data. */
    void           *ptr;
} ucx_regdestr;

#ifdef __cplusplus
extern "C"
#endif
void ucx_mempool_shared_destr(void* ptr) {
    ucx_regdestr *rd = (ucx_regdestr*)ptr;
    rd->destructor(rd->ptr);
}

UcxMempool *ucx_mempool_new(size_t n) {
    UcxMempool *pool = (UcxMempool*)malloc(sizeof(UcxMempool));
    if (!pool) {
        return NULL;
    }
    
    pool->data = (void**) malloc(n * sizeof(void*));
    if (pool->data == NULL) {
        free(pool);
        return NULL;
    }
    
    pool->ndata = 0;
    pool->size = n;
    
    UcxAllocator *allocator = (UcxAllocator*)malloc(sizeof(UcxAllocator));
    if(!allocator) {
        free(pool->data);
        free(pool);
        return NULL;
    }
    allocator->malloc = (ucx_allocator_malloc)ucx_mempool_malloc;
    allocator->calloc = (ucx_allocator_calloc)ucx_mempool_calloc;
    allocator->realloc = (ucx_allocator_realloc)ucx_mempool_realloc;
    allocator->free = (ucx_allocator_free)ucx_mempool_free;
    allocator->pool = pool;
    pool->allocator = allocator;
    
    return pool;
}

int ucx_mempool_chcap(UcxMempool *pool, size_t newcap) {
    if (newcap < pool->ndata) {
        return 1;
    }
    
    void **data = (void**) realloc(pool->data, newcap*sizeof(void*));
    if (data) {
        pool->data = data; 
        pool->size = newcap;
        return 0;
    } else {
        return 1;
    }
}

void *ucx_mempool_malloc(UcxMempool *pool, size_t n) {
    if (pool->ndata >= pool->size) {
        size_t newcap = pool->size*2;
        if (newcap < pool->size || ucx_mempool_chcap(pool, newcap)) {
            return NULL;
        }
    }

    void *p = malloc(sizeof(ucx_destructor) + n);
    ucx_memchunk *mem = (ucx_memchunk*)p;
    if (!mem) {
        return NULL;
    }

    mem->destructor = NULL;
    pool->data[pool->ndata] = mem;
    pool->ndata++;

    return &(mem->c);
}

void *ucx_mempool_calloc(UcxMempool *pool, size_t nelem, size_t elsize) {
    void *ptr = ucx_mempool_malloc(pool, nelem*elsize);
    if (!ptr) {
        return NULL;
    }
    memset(ptr, 0, nelem * elsize);
    return ptr;
}

void *ucx_mempool_realloc(UcxMempool *pool, void *ptr, size_t n) {
    char *mem = ((char*)ptr) - sizeof(ucx_destructor);
    char *newm = (char*) realloc(mem, n + sizeof(ucx_destructor));
    if (!newm) {
        return NULL;
    }
    if (mem != newm) {
        for(size_t i=0 ; i < pool->ndata ; i++) {
            if(pool->data[i] == mem) {
                pool->data[i] = newm;
                return newm + sizeof(ucx_destructor);
            }
        }
        fprintf(stderr, "FATAL: 0x%08" PRIxPTR" not in mpool 0x%08" PRIxPTR"\n",
          (intptr_t)ptr, (intptr_t)pool);
        abort();
    } else {
        return newm + sizeof(ucx_destructor);
    }
}

void ucx_mempool_free(UcxMempool *pool, void *ptr) {
    ucx_memchunk *chunk = (ucx_memchunk*)((char*)ptr-sizeof(ucx_destructor));
    for(size_t i=0 ; i<pool->ndata ; i++) {
        if(chunk == pool->data[i]) {
            if(chunk->destructor != NULL) {
                chunk->destructor(&(chunk->c));
            }
            free(chunk);
            size_t last_index = pool->ndata - 1;
            if(i != last_index) {
                pool->data[i] = pool->data[last_index];
                pool->data[last_index] = NULL;
            }
            pool->ndata--;
            return;
        }
    }
    fprintf(stderr, "FATAL: 0x%08" PRIxPTR" not in mpool 0x%08" PRIxPTR"\n",
            (intptr_t)ptr, (intptr_t)pool);
    abort();
}

void ucx_mempool_destroy(UcxMempool *pool) {
    ucx_memchunk *chunk;
    for(size_t i=0 ; i<pool->ndata ; i++) {
        chunk = (ucx_memchunk*) pool->data[i];
        if(chunk) {
            if(chunk->destructor) {
                chunk->destructor(&(chunk->c));
            }
            free(chunk);
        }
    }
    free(pool->data);
    free(pool->allocator);
    free(pool);
}

void ucx_mempool_set_destr(void *ptr, ucx_destructor func) {
    *(ucx_destructor*)((char*)ptr-sizeof(ucx_destructor)) = func;
}

void ucx_mempool_reg_destr(UcxMempool *pool, void *ptr, ucx_destructor destr) {
    ucx_regdestr *rd = (ucx_regdestr*)ucx_mempool_malloc(
            pool,
            sizeof(ucx_regdestr));
    rd->destructor = destr;
    rd->ptr = ptr;
    ucx_mempool_set_destr(rd, ucx_mempool_shared_destr);
}

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