view src/fetchlist.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 53cfa011a08c
children fed1334d766b
line wrap: on
line source

/*
  fetchlist.c

  $Id: fetchlist.c 68 2000-05-12 17:28:07Z enz $
*/

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

#include <stdio.h>
#include "fetchlist.h"
#include "configfile.h"
#include "log.h"
#include "util.h"
#include "portable.h"

struct Elem
{
    Str name;
    FetchMode mode;
};

static struct Fetchlist
{
    struct Elem *elem;
    int size;
    int max;
} fetchlist = { NULL, 0, 0 };

static const char *
getFile( void )
{
    static Str file;
    snprintf( file, MAXCHAR, "%s/fetchlist", Cfg_spoolDir() );
    return file;
}

static void
clearList( void )
{
    fetchlist.size = 0;
}

static int
compareElem( const void *elem1, const void *elem2 )
{
    const struct Elem* e1 = (const struct Elem*)elem1; 
    const struct Elem* e2 = (const struct Elem*)elem2;
    return strcmp( e1->name, e2->name );
}

static struct Elem *
searchElem( const char *name )
{
    int i;
    
    for ( i = 0; i < fetchlist.size; ++i )
        if ( strcmp( name, fetchlist.elem[ i ].name ) == 0 )
            return &fetchlist.elem[ i ];
    return NULL;
}

static void
appGrp( const char *name, FetchMode mode )
{
    struct Elem elem;

    if ( fetchlist.max < fetchlist.size + 1 )
    {
        if ( ! ( fetchlist.elem
                 = realloc( fetchlist.elem,
                            ( fetchlist.max + 50 )
                            * sizeof( fetchlist.elem[ 0 ] ) ) ) )
        {
            Log_err( "Could not realloc fetchlist" );
            exit( EXIT_FAILURE );
        }
        fetchlist.max += 50;
    }
    strcpy( elem.name, name );
    elem.mode = mode;
    fetchlist.elem[ fetchlist.size++ ] = elem;
}

void
Fetchlist_read( void )
{
    FILE *f;
    const char *file = getFile();
    char *p;
    FetchMode mode = OVER;
    Bool valid;
    int ret;
    Str line, grp, modeStr;

    Log_dbg( "Reading %s", file );
    clearList();
    if ( ! ( f = fopen( file, "r" ) ) )
    {
        Log_inf( "No file %s", file );
        return;
    }
    while ( fgets( line, MAXCHAR, f ) )
    {
        p = Utl_stripWhiteSpace( line );
        if ( *p == '#' || *p == '\0' )
            continue;
        ret = sscanf( p, "%s %s", grp, modeStr );
        valid = TRUE;
        if ( ret < 1 || ret > 2 )
            valid = FALSE;
        else if ( ret >= 2 )
        {
            if ( strcmp( modeStr, "full" ) == 0 )
                mode = FULL;
            else if ( strcmp( modeStr, "thread" ) == 0 )
                mode = THREAD;
            else if ( strcmp( modeStr, "over" ) == 0 )
                mode = OVER;
            else
                valid = FALSE;
        }
        if ( ! valid )
        {
            Log_err( "Invalid entry in %s: %s", file, line );
            continue;
        }
        appGrp( grp, mode );
    }
    fclose( f );
}

Bool
Fetchlist_write( void )
{
    int i;
    FILE *f;
    const char *file = getFile();
    const char *modeStr = "";

    qsort( fetchlist.elem, (size_t)fetchlist.size,
           sizeof( fetchlist.elem[ 0 ] ), compareElem );
    if ( ! ( f = fopen( file, "w" ) ) )
    {
        Log_err( "Could not open %s for writing", file );
        return FALSE;
    }
    for ( i = 0; i < fetchlist.size; ++i )
    {
        switch ( fetchlist.elem[ i ].mode )
        {
        case FULL:
            modeStr = "full"; break;
        case THREAD:
            modeStr = "thread"; break;
        case OVER:
            modeStr = "over"; break;
        }
        fprintf( f, "%s %s\n", fetchlist.elem[ i ].name, modeStr );
    }
    fclose( f );
    return TRUE;
}

int
Fetchlist_size( void )
{
    return fetchlist.size;
}

Bool
Fetchlist_contains( const char *name )
{
    return ( searchElem( name ) != NULL );
}

Bool
Fetchlist_element( const char **name, FetchMode *mode, int idx )
{
    if ( idx < 0 || idx >= fetchlist.size )
        return FALSE;
    *name = fetchlist.elem[ idx ].name;
    *mode = fetchlist.elem[ idx ].mode;
    return TRUE;
}

Bool
Fetchlist_add( const char *name, FetchMode mode )
{
    struct Elem *elem = searchElem( name );
    if ( elem == NULL )
    {
        appGrp( name, mode );
        return TRUE;
    }
    strcpy( elem->name, name );
    elem->mode = mode;
    return FALSE;
}

Bool
Fetchlist_remove( const char *name )
{
    struct Elem *elem = searchElem( name );
    if ( elem == NULL )
        return FALSE;
    *elem = fetchlist.elem[ fetchlist.size - 1 ];
    --fetchlist.size;
    return TRUE;
}