memory.c

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/* src/interfaces/ecpg/ecpglib/memory.c */
 
#define POSTGRES_ECPG_INTERNAL
#include "postgres_fe.h"
 
#include "ecpg-pthread-win32.h"
#include "ecpgerrno.h"
#include "ecpglib.h"
#include "ecpglib_extern.h"
#include "ecpgtype.h"
 
void
ecpg_free(void *ptr)
{
    free(ptr);
}
 
char *
ecpg_alloc(long size, int lineno)
{
    char       *new = (char *) calloc(1L, size);
 
    if (!new)
    {
        ecpg_raise(lineno, ECPG_OUT_OF_MEMORY, ECPG_SQLSTATE_ECPG_OUT_OF_MEMORY, NULL);
        return NULL;
    }
 
    return new;
}
 
char *
ecpg_realloc(void *ptr, long size, int lineno)
{
    char       *new = (char *) realloc(ptr, size);
 
    if (!new)
    {
        ecpg_raise(lineno, ECPG_OUT_OF_MEMORY, ECPG_SQLSTATE_ECPG_OUT_OF_MEMORY, NULL);
        return NULL;
    }
 
    return new;
}
 
/*
 * Wrapper for strdup(), with NULL in input treated as a correct case.
 *
 * "alloc_failed" can be optionally specified by the caller to check for
 * allocation failures.  The caller is responsible for its initialization,
 * as ecpg_strdup() may be called repeatedly across multiple allocations.
 */
char *
ecpg_strdup(const char *string, int lineno, bool *alloc_failed)
{
    char       *new;
 
    if (string == NULL)
        return NULL;
 
    new = strdup(string);
    if (!new)
    {
        if (alloc_failed)
            *alloc_failed = true;
        ecpg_raise(lineno, ECPG_OUT_OF_MEMORY, ECPG_SQLSTATE_ECPG_OUT_OF_MEMORY, NULL);
        return NULL;
    }
 
    return new;
}
 
/* keep a list of memory we allocated for the user */
struct auto_mem
{
    void       *pointer;
    struct auto_mem *next;
};
 
static pthread_key_t auto_mem_key;
static pthread_once_t auto_mem_once = PTHREAD_ONCE_INIT;
 
static void
auto_mem_destructor(void *arg)
{
    (void) arg;                 /* keep the compiler quiet */
    ECPGfree_auto_mem();
}
 
static void
auto_mem_key_init(void)
{
    pthread_key_create(&auto_mem_key, auto_mem_destructor);
}
 
static struct auto_mem *
get_auto_allocs(void)
{
    pthread_once(&auto_mem_once, auto_mem_key_init);
    return (struct auto_mem *) pthread_getspecific(auto_mem_key);
}
 
static void
set_auto_allocs(struct auto_mem *am)
{
    pthread_setspecific(auto_mem_key, am);
}
 
char *
ecpg_auto_alloc(long size, int lineno)
{
    void       *ptr = ecpg_alloc(size, lineno);
 
    if (!ptr)
        return NULL;
 
    if (!ecpg_add_mem(ptr, lineno))
    {
        ecpg_free(ptr);
        return NULL;
    }
    return ptr;
}
 
bool
ecpg_add_mem(void *ptr, int lineno)
{
    struct auto_mem *am = (struct auto_mem *) ecpg_alloc(sizeof(struct auto_mem), lineno);
 
    if (!am)
        return false;
 
    am->pointer = ptr;
    am->next = get_auto_allocs();
    set_auto_allocs(am);
    return true;
}
 
void
ECPGfree_auto_mem(void)
{
    struct auto_mem *am = get_auto_allocs();
 
    /* free all memory we have allocated for the user */
    if (am)
    {
        do
        {
            struct auto_mem *act = am;
 
            am = am->next;
            ecpg_free(act->pointer);
            ecpg_free(act);
        } while (am);
        set_auto_allocs(NULL);
    }
}
 
void
ecpg_clear_auto_mem(void)
{
    struct auto_mem *am = get_auto_allocs();
 
    /* only free our own structure */
    if (am)
    {
        do
        {
            struct auto_mem *act = am;
 
            am = am->next;
            ecpg_free(act);
        } while (am);
        set_auto_allocs(NULL);
    }
}