/* Define _XOPEN_SOURCE to get tempnam prototype with glibc et al --
   more general than _INCLUDE_XOPEN_SOURCE used elsewhere `for HP-UX'.  */
#define _XOPEN_SOURCE 1
#include "f2c.h"
#include "fio.h"
#include <string.h>
#ifndef NON_POSIX_STDIO
#ifdef MSDOS
#include "io.h"
#else
#include "unistd.h"	/* for access */
#endif
#endif

#ifdef KR_headers
extern char *malloc();
#ifdef NON_ANSI_STDIO
extern char *mktemp();
#endif
extern integer f_clos();
#else
#undef abs
#undef min
#undef max
#include <stdlib.h>
extern int f__canseek(FILE*);
extern integer f_clos(cllist*);
#endif

#ifdef NON_ANSI_RW_MODES
char *f__r_mode[2] = {"r", "r"};
char *f__w_mode[4] = {"w", "w", "r+w", "r+w"};
#else
char *f__r_mode[2] = {"rb", "r"};
char *f__w_mode[4] = {"wb", "w", "r+b", "r+"};
#endif

 static char f__buf0[400], *f__buf = f__buf0;
 int f__buflen = (int)sizeof(f__buf0);

 static void
#ifdef KR_headers
f__bufadj(n, c) int n, c;
#else
f__bufadj(int n, int c)
#endif
{
	unsigned int len;
	char *nbuf, *s, *t, *te;

	if (f__buf == f__buf0)
		f__buflen = 1024;
	while(f__buflen <= n)
		f__buflen <<= 1;
	len = (unsigned int)f__buflen;
	if (len != f__buflen || !(nbuf = (char*)malloc(len)))
		f__fatal(113, "malloc failure");
	s = nbuf;
	t = f__buf;
	te = t + c;
	while(t < te)
		*s++ = *t++;
	if (f__buf != f__buf0)
		free(f__buf);
	f__buf = nbuf;
	}

 int
#ifdef KR_headers
f__putbuf(c) int c;
#else
f__putbuf(int c)
#endif
{
	char *s, *se;
	int n;

	if (f__hiwater > f__recpos)
		f__recpos = f__hiwater;
	n = f__recpos + 1;
	if (n >= f__buflen)
		f__bufadj(n, f__recpos);
	s = f__buf;
	se = s + f__recpos;
	if (c)
		*se++ = c;
	*se = 0;
	for(;;) {
		fputs(s, f__cf);
		s += strlen(s);
		if (s >= se)
			break;	/* normally happens the first time */
		putc(*s++, f__cf);
		}
	return 0;
	}

 void
#ifdef KR_headers
x_putc(c)
#else
x_putc(int c)
#endif
{
	if (f__recpos >= f__buflen)
		f__bufadj(f__recpos, f__buflen);
	f__buf[f__recpos++] = c;
	}

#define opnerr(f,m,s) \
  do {if(f) {f__init &= ~2; errno= m;} else opn_err(m,s,a); return(m);} while(0)

 static void
#ifdef KR_headers
opn_err(m, s, a) int m; char *s; olist *a;
#else
opn_err(int m, char *s, olist *a)
#endif
{
	if (a->ofnm) {
		/* supply file name to error message */
		if (a->ofnmlen >= f__buflen)
			f__bufadj((int)a->ofnmlen, 0);
		g_char(a->ofnm, a->ofnmlen, f__curunit->ufnm = f__buf);
		}
	f__fatal(m, s);
	}

#ifdef KR_headers
integer f_open(a) olist *a;
#else
integer f_open(olist *a)
#endif
{	unit *b;
	integer rv;
	char buf[256], *s, *env;
	cllist x;
	int ufmt;
	FILE *tf;
	int fd, len;
#ifndef NON_UNIX_STDIO
	int n;
#endif
	if(f__init != 1) f_init();
	f__external = 1;
	if(a->ounit>=MXUNIT || a->ounit<0)
		err(a->oerr,101,"open");
	f__curunit = b = &f__units[a->ounit];
	if(b->ufd) {
		if(a->ofnm==0)
		{
		same:	if (a->oblnk)
				b->ublnk = *a->oblnk == 'z' || *a->oblnk == 'Z';
			return(0);
		}
#ifdef NON_UNIX_STDIO
		if (b->ufnm
		 && strlen(b->ufnm) == a->ofnmlen
		 && !strncmp(b->ufnm, a->ofnm, (unsigned)a->ofnmlen))
			goto same;
#else
		g_char(a->ofnm,a->ofnmlen,buf);
		if (f__inode(buf,&n) == b->uinode && n == b->udev)
			goto same;
#endif
		x.cunit=a->ounit;
		x.csta=0;
		x.cerr=a->oerr;
		if ((rv = f_clos(&x)) != 0)
			return rv;
		}
	b->url = (int)a->orl;
	b->ublnk = a->oblnk && (*a->oblnk == 'z' || *a->oblnk == 'Z');
	if(a->ofm==0)
	{	if(b->url>0) b->ufmt=0;
		else b->ufmt=1;
	}
	else if(*a->ofm=='f' || *a->ofm == 'F') b->ufmt=1;
	else b->ufmt=0;
	ufmt = b->ufmt;
#ifdef url_Adjust
	if (b->url && !ufmt)
		url_Adjust(b->url);
#endif
	if (a->ofnm) {
		g_char(a->ofnm,a->ofnmlen,buf);
		if (!buf[0])
			opnerr(a->oerr,107,"open");
		}
	else
		sprintf(buf, "fort.%ld", (long)a->ounit);
	b->uscrtch = 0;
	b->uend=0;
	b->uwrt = 0;
	b->ufd = 0;
	b->urw = 3;
	switch(a->osta ? *a->osta : 'u')
	{
	case 'o':
	case 'O':
#ifdef NON_POSIX_STDIO
		if (!(tf = fopen(buf,"r")))
			opnerr(a->oerr,errno,"open");
		fclose(tf);
#else
		if (access(buf,0))
			opnerr(a->oerr,errno,"open");
#endif
		break;
	 case 's':
	 case 'S':
		b->uscrtch=1;
#ifdef HAVE_MKSTEMP             /* Allow use of TMPDIR preferentially. */
		env = getenv("TMPDIR");
		if (!env) env = getenv("TEMP");
		if (!env) env = "/tmp";
		len = strlen(env);
		if (len > 256 - sizeof "/tmp.FXXXXXX")
		  err (a->oerr, 132, "open");
		strcpy(buf, env);
		strcat(buf, "/tmp.FXXXXXX");
		fd = mkstemp(buf);
		if (fd == -1 || close(fd))
		  err (a->oerr, 132, "open");
#else /* ! defined (HAVE_MKSTEMP) */
#ifdef HAVE_TEMPNAM		/* Allow use of TMPDIR preferentially. */
		s = tempnam (0, buf);
		if (strlen (s) >= sizeof (buf))
		  err (a->oerr, 132, "open");
		(void) strcpy (buf, s);
		free (s);
#else /* ! defined (HAVE_TEMPNAM) */
#ifdef _POSIX_SOURCE
		tmpnam(buf);
#else
		(void) strcpy(buf,"tmp.FXXXXXX");
		(void) mktemp(buf);
#endif
#endif /* ! defined (HAVE_TEMPNAM) */
#endif /* ! defined (HAVE_MKSTEMP) */
		goto replace;
	case 'n':
	case 'N':
#ifdef NON_POSIX_STDIO
		if ((tf = fopen(buf,"r")) || (tf = fopen(buf,"a"))) {
			fclose(tf);
			opnerr(a->oerr,128,"open");
			}
#else
		if (!access(buf,0))
			opnerr(a->oerr,128,"open");
#endif
		/* no break */
	case 'r':	/* Fortran 90 replace option */
	case 'R':
 replace:
		if (tf = fopen(buf,f__w_mode[0]))
			fclose(tf);
	}

	b->ufnm=(char *) malloc((unsigned int)(strlen(buf)+1));
	if(b->ufnm==NULL) opnerr(a->oerr,113,"no space");
	(void) strcpy(b->ufnm,buf);
	if ((s = a->oacc) && b->url)
		ufmt = 0;
	if(!(tf = fopen(buf, f__w_mode[ufmt|2]))) {
		if (tf = fopen(buf, f__r_mode[ufmt]))
			b->urw = 1;
		else if (tf = fopen(buf, f__w_mode[ufmt])) {
			b->uwrt = 1;
			b->urw = 2;
			}
		else
			err(a->oerr, errno, "open");
		}
	b->useek = f__canseek(b->ufd = tf);
#ifndef NON_UNIX_STDIO
	if((b->uinode = f__inode(buf,&b->udev)) == -1)
		opnerr(a->oerr,108,"open");
#endif
	if(b->useek)
		if (a->orl)
			rewind(b->ufd);
		else if ((s = a->oacc) && (*s == 'a' || *s == 'A')
			&& fseek(b->ufd, 0L, SEEK_END))
				opnerr(a->oerr,129,"open");
	return(0);
}
#ifdef KR_headers
fk_open(seq,fmt,n) ftnint n;
#else
fk_open(int seq, int fmt, ftnint n)
#endif
{	char nbuf[10];
	olist a;
	int rtn;
	int save_init;

	(void) sprintf(nbuf,"fort.%ld",(long)n);
	a.oerr=1;
	a.ounit=n;
	a.ofnm=nbuf;
	a.ofnmlen=strlen(nbuf);
	a.osta=NULL;
	a.oacc= seq==SEQ?"s":"d";
	a.ofm = fmt==FMT?"f":"u";
	a.orl = seq==DIR?1:0;
	a.oblnk=NULL;
	save_init = f__init;
	f__init &= ~2;
	rtn = f_open(&a);
	f__init = save_init | 1;
	return rtn;
}