mirror of https://github.com/lua/lua
118 lines
2.0 KiB
C
118 lines
2.0 KiB
C
/*
|
|
* zio.c
|
|
* a generic input stream interface
|
|
* $Id: zio.c,v 1.5 1997/06/13 13:49:16 lhf Exp $
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include "zio.h"
|
|
|
|
#ifdef POPEN
|
|
FILE *popen();
|
|
int pclose();
|
|
#else
|
|
#define popen(x,y) NULL /* that is, popen always fails */
|
|
#define pclose(x) (-1)
|
|
#endif
|
|
|
|
/* ----------------------------------------------------- memory buffers --- */
|
|
|
|
static int zmfilbuf(ZIO* z)
|
|
{
|
|
return EOZ;
|
|
}
|
|
|
|
static int zmclose(ZIO* z)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
ZIO* zmopen(ZIO* z, char* b, int size)
|
|
{
|
|
if (b==NULL) return NULL;
|
|
z->n=size;
|
|
z->p= (unsigned char *)b;
|
|
z->filbuf=zmfilbuf;
|
|
z->close=zmclose;
|
|
z->u=NULL;
|
|
return z;
|
|
}
|
|
|
|
/* ------------------------------------------------------------ strings --- */
|
|
|
|
ZIO* zsopen(ZIO* z, char* s)
|
|
{
|
|
if (s==NULL) return NULL;
|
|
return zmopen(z,s,strlen(s));
|
|
}
|
|
|
|
/* -------------------------------------------------------------- FILEs --- */
|
|
|
|
static int zffilbuf(ZIO* z)
|
|
{
|
|
int n=fread(z->buffer,1,ZBSIZE,z->u);
|
|
if (n==0) return EOZ;
|
|
z->n=n-1;
|
|
z->p=z->buffer;
|
|
return *(z->p++);
|
|
}
|
|
|
|
static int zfclose(ZIO* z)
|
|
{
|
|
if (z->u==stdin) return 0;
|
|
return fclose(z->u);
|
|
}
|
|
|
|
ZIO* zFopen(ZIO* z, FILE* f)
|
|
{
|
|
if (f==NULL) return NULL;
|
|
z->n=0;
|
|
z->p=z->buffer;
|
|
z->filbuf=zffilbuf;
|
|
z->close=zfclose;
|
|
z->u=f;
|
|
return z;
|
|
}
|
|
|
|
ZIO* zfopen(ZIO* z, char* s, char* m)
|
|
{
|
|
return zFopen(z,fopen(s,m));
|
|
}
|
|
|
|
/* -------------------------------------------------------------- pipes --- */
|
|
|
|
static int zpclose(ZIO* z)
|
|
{
|
|
return pclose(z->u);
|
|
}
|
|
|
|
ZIO* zpopen(ZIO* z, char* s, char* m)
|
|
{
|
|
z=zFopen(z,popen(s,m));
|
|
if (z==NULL) return NULL;
|
|
z->close=zpclose;
|
|
return z;
|
|
}
|
|
|
|
/* --------------------------------------------------------------- read --- */
|
|
int zread(ZIO *z, void *b, int n)
|
|
{
|
|
while (n) {
|
|
int m;
|
|
if (z->n == 0) {
|
|
if (z->filbuf(z) == EOZ)
|
|
return n; /* retorna quantos faltaram ler */
|
|
zungetc(z); /* poe o resultado de filbuf no buffer */
|
|
}
|
|
m = (n <= z->n) ? n : z->n; /* minimo de n e z->n */
|
|
memcpy(b, z->p, m);
|
|
z->n -= m;
|
|
z->p += m;
|
|
b = (char *)b + m;
|
|
n -= m;
|
|
}
|
|
return 0;
|
|
}
|