nopen.c

/* nopen.c */

/* Network open functions (nopen and fnopen) */

/* $Id$ */

/****************************************************************************
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 * Copyright 2004 Rob Swindell - http://www.synchro.net/copyright.html		*
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#include "sbbs.h"
#include "crc32.h"

/****************************************************************************/
/* Network open function. Opens all files DENYALL and retries LOOP_NOPEN    */
/* number of times if the attempted file is already open or denying access  */
/* for some other reason.	All files are opened in BINARY mode.			*/
/****************************************************************************/
int nopen(const char* str, int access)
{
	int file,share,count=0;

    if(access&O_DENYNONE) {
        share=SH_DENYNO;
        access&=~O_DENYNONE; }
    else if(access==O_RDONLY) share=SH_DENYWR;
    else share=SH_DENYRW;
	if(!(access&O_TEXT))
		access|=O_BINARY;
    while(((file=sopen(str,access,share,S_IREAD|S_IWRITE))==-1)
        && (errno==EACCES || errno==EAGAIN || errno==EDEADLOCK) && count++<LOOP_NOPEN)
        if(count)
            mswait(100);
    return(file);
}
/****************************************************************************/
/* This function performs an nopen, but returns a file stream with a buffer */
/* allocated.																*/
/****************************************************************************/
FILE* fnopen(int* fd, const char* str, int access)
{
	char	mode[128];
	int		file;
	FILE *	stream;

    if((file=nopen(str,access))==-1)
        return(NULL);

    if(fd!=NULL)
        *fd=file;

    if(access&O_APPEND) {
        if((access&O_RDWR)==O_RDWR)
            strcpy(mode,"a+");
        else
            strcpy(mode,"a"); 
	} else if(access&(O_TRUNC|O_WRONLY)) {
		if((access&O_RDWR)==O_RDWR)
			strcpy(mode,"w+");
		else
			strcpy(mode,"w");
	} else {
        if((access&O_RDWR)==O_RDWR)
            strcpy(mode,"r+");
        else
            strcpy(mode,"r"); 
	}
    stream=fdopen(file,mode);
    if(stream==NULL) {
        close(file);
        return(NULL); 
	}
    setvbuf(stream,NULL,_IOFBF,FNOPEN_BUF_SIZE);
    return(stream);
}

BOOL ftouch(const char* fname)
{
	int file;

	if((file=nopen(fname,O_WRONLY|O_CREAT))<0)
		return(FALSE);
	close(file);

	return(TRUE);
}

BOOL fmutex(const char* fname, const char* text)
{
	int file;
#if !defined(NO_SOCKET_SUPPORT)
	char hostname[128];
	if(text==NULL && gethostname(hostname,sizeof(hostname))==0)
		text=hostname;
#endif

	if((file=open(fname,O_CREAT|O_WRONLY|O_EXCL,S_IREAD|S_IWRITE))<0)
		return(FALSE);
	if(text!=NULL)
		write(file,text,strlen(text));
	close(file);
	return(TRUE);
}