codexlib/zip/zip.c

#pragma prototyped

/*
 * zip decoder
 * this is a wrapper method for the PKZIP { shrink reduce implode deflate }
 */

#include "zip.h"

#define ID(a,b)     (((a)<<8)|(b))

static int
zip_open(Codex_t* p, char* const args[], Codexnum_t flags)
{
    const char* name;
    const char* method;

    name = args[0];
    if (!(method = args[2]))
    {
        if (p->disc->errorf)
            (*p->disc->errorf)(NiL, p->disc, 2, "%s: method parameter expected", name);
        return -1;
    }
    switch (ID(method[0], method[1]))
    {
    case ID('0',0):
    case ID('c','o'):
        p->meth = 0;
        return 0;
    case ID('1',0):
    case ID('s','h'):
        p->meth = &codex_zip_shrink;
        break;
    case ID('2',0):
    case ID('3',0):
    case ID('4',0):
    case ID('5',0):
    case ID('r','e'):
        p->meth = &codex_zip_reduce;
        break;
    case ID('6',0):
    case ID('e','x'):
    case ID('i','m'):
        p->meth = &codex_zip_implode;
        break;
    case ID('8',0):
    case ID('d','e'):
    case ID('i','n'):
    case ID('m','s'):
    case ID('C','K'):
    case ID('M','S'):
        p->meth = &codex_zip_deflate;
        break;
    default:
        if (p->disc->errorf)
            (*p->disc->errorf)(NiL, p->disc, 2, "%s: %s: unknown method", name, method);
        return 0;
    }
    return (*p->meth->openf)(p, args, flags);
}

Codexmeth_t codex_zip =
{
    "zip",
    "zip compression. The first parameter is the PKZIP compression"
    " method.",
    "[+copy|0?No compression.]"
    "[+shrink|1?Shrink compression.]"
    "[+reduce|2|3|4|5?Reduce compression.]"
    "[+implode|6?Implode compression.]"
    "[+deflate|8?Deflate compression.]",
    CODEX_DECODE|CODEX_ENCODE|CODEX_COMPRESS,
    0,
    0,
    zip_open,
    0,
    0,
    0,
    0,
    0,
    0,
    0,
    0,
    0,
    0,
    CODEXNEXT(zip)
};

CODEXLIB(zip)