view src/dynamicstring.c @ 165:8ea6b5ddc5a5 noffle

[svn] * src/lock.h,src/lock.c,src/noffle.c: Add lazy lock release. Only release the lock and close the databases if (a) another process signals us SIGUSR1 indicating it wants the lock, or (b) it is explicitly requested by a call to new function Lock_syncDatabases(). When waiting for the lock, SIGUSR1 the holding process every second. This is all an attempt to minimise the number of times we need to close and open the database. When (ha!) the database is replaced by something that can handle multiple simultaneous writers (with appropriate locking) this won't be necessary.
author bears
date Thu, 25 Jan 2001 13:38:31 +0000
parents e612b263934f
children 24d4cd032da5
line wrap: on
line source

/*
  dynamicstring.c

  $Id: dynamicstring.c 65 2000-05-12 16:52:41Z enz $
*/

#if HAVE_CONFIG_H
#include <config.h>
#endif

#include "dynamicstring.h"

#include <sys/types.h>
#include "log.h"
#include "portable.h"

struct DynStr
{
    int len; /* Current length (without trailing '\0') */
    int max; /* Max length that fits into buffer (incl. trailing '\0') */
    char *str;
};

static void
reallocStr( DynStr *self, int max )
{
    ASSERT( max >= 0 );
    if ( max <= self->max )
        return;
    if ( ! ( self->str = (char *)realloc( self->str, (size_t)max ) ) )
    {
        Log_err( "Realloc of DynStr failed" );
        exit( EXIT_FAILURE );
    } 
    if ( self->max == 0 ) /* First allocation? */
        *(self->str) = '\0';
    self->max = max;
}

DynStr *
new_DynStr( int reserve )
{
    DynStr *s;
    
    if ( ! ( s = malloc( sizeof( DynStr ) ) ) )
    {
        Log_err( "Allocation of DynStr failed" );
        exit( EXIT_FAILURE );
    }
    s->len = 0;
    s->max = 0;
    s->str = NULL;
    if ( reserve > 0 )
        reallocStr( s, reserve + 1 );
    return s;
}

void
del_DynStr( DynStr *self )
{
    if ( ! self )
        return;
    free( self->str );
    self->str = NULL;
    free( self );
}

int
DynStr_len( const DynStr *self )
{
    return self->len;
}

const char *
DynStr_str( const DynStr *self )
{
    return self->str;
}

void
DynStr_app( DynStr *self, const char *s )
{
    int len;

    len = strlen( s );
    if ( self->len + len + 1 > self->max )
        reallocStr( self, self->len * 2 + len + 1 );
    strcpy( self->str + self->len, s );
    self->len += len;
}

void
DynStr_appDynStr( DynStr *self, const DynStr *s )
{
    if ( self->len + s->len + 1 > self->max )
        reallocStr( self, self->len * 2 + s->len + 1 );
    memcpy( self->str + self->len, s->str, (size_t)s->len + 1 );
    self->len += s->len;
}

void
DynStr_appLn( DynStr *self, const char *s )
{
    DynStr_app( self, s );
    DynStr_app( self, "\n" );
}

void
DynStr_appN( DynStr *self, const char *s, int n )
{
    int len = self->len;

    ASSERT( n >= 0 );
    if ( len + n + 1 > self->max )
        reallocStr( self, len * 2 + n + 1 );
    strncat( self->str + len, s, (size_t)n );
    self->len = len + strlen( self->str + len );
}

void
DynStr_clear( DynStr *self )
{
    self->len = 0;
    if ( self->max > 0 )
        *(self->str) = '\0';
}