libf2c/libI77/endfile.c

   1 #include "config.h"
   2 #include "f2c.h"
   3 #include "fio.h"
   4
   5 #include <sys/types.h>
   6 #include <unistd.h>
   7
   8 #undef abs
   9 #undef min
  10 #undef max
  11 #include <stdlib.h>
  12 #include <string.h>
  13
  14 extern char *f__r_mode[], *f__w_mode[];
  15
  16 integer f_end(alist *a)
  17 {
  18         unit *b;
  19         FILE *tf;
  20
  21         if (f__init & 2)
  22                 f__fatal (131, "I/O recursion");
  23         if(a->aunit>=MXUNIT || a->aunit<0) err(a->aerr,101,"endfile");
  24         b = &f__units[a->aunit];
  25         if(b->ufd==NULL) {
  26                 char nbuf[10];
  27                 sprintf(nbuf,"fort.%ld",(long)a->aunit);
  28                 if (tf = fopen(nbuf, f__w_mode[0]))
  29                         fclose(tf);
  30                 return(0);
  31                 }
  32         b->uend=1;
  33         return(b->useek ? t_runc(a) : 0);
  34 }
  35
  36 #ifndef HAVE_FTRUNCATE
  37  static int
  38 copy(FILE *from, register long len, FILE *to)
  39 {
  40         int len1;
  41         char buf[BUFSIZ];
  42
  43         while(fread(buf, len1 = len > BUFSIZ ? BUFSIZ : (int)len, 1, from)) {
  44                 if (!fwrite(buf, len1, 1, to))
  45                         return 1;
  46                 if ((len -= len1) <= 0)
  47                         break;
  48                 }
  49         return 0;
  50         }
  51 #endif /* !defined(HAVE_FTRUNCATE) */
  52
  53  int
  54 t_runc(alist *a)
  55 {
  56         off_t loc, len;
  57         unit *b;
  58         int rc;
  59         FILE *bf;
  60 #ifndef HAVE_FTRUNCATE
  61         FILE *tf;
  62 #endif /* !defined(HAVE_FTRUNCATE) */
  63
  64         b = &f__units[a->aunit];
  65         if(b->url)
  66                 return(0);      /*don't truncate direct files*/
  67         loc=FTELL(bf = b->ufd);
  68         FSEEK(bf,0,SEEK_END);
  69         len=FTELL(bf);
  70         if (loc >= len || b->useek == 0 || b->ufnm == NULL)
  71                 return(0);
  72 #ifndef HAVE_FTRUNCATE
  73         rc = 0;
  74         fclose(b->ufd);
  75         if (!loc) {
  76                 if (!(bf = fopen(b->ufnm, f__w_mode[b->ufmt])))
  77                         rc = 1;
  78                 if (b->uwrt)
  79                         b->uwrt = 1;
  80                 goto done;
  81                 }
  82         if (!(bf = fopen(b->ufnm, f__r_mode[0]))
  83          || !(tf = tmpfile())) {
  84 #ifdef NON_UNIX_STDIO
  85  bad:
  86 #endif
  87                 rc = 1;
  88                 goto done;
  89                 }
  90         if (copy(bf, loc, tf)) {
  91  bad1:
  92                 rc = 1;
  93                 goto done1;
  94                 }
  95         if (!(bf = freopen(b->ufnm, f__w_mode[0], bf)))
  96                 goto bad1;
  97         FSEEK(tf, 0, SEEK_SET);
  98         if (copy(tf, loc, bf))
  99                 goto bad1;
 100         b->uwrt = 1;
 101         b->urw = 2;
 102 #ifdef NON_UNIX_STDIO
 103         if (b->ufmt) {
 104                 fclose(bf);
 105                 if (!(bf = fopen(b->ufnm, f__w_mode[3])))
 106                         goto bad;
 107                 FSEEK(bf,0,SEEK_END);
 108                 b->urw = 3;
 109                 }
 110 #endif
 111 done1:
 112         fclose(tf);
 113 done:
 114         f__cf = b->ufd = bf;
 115 #else  /* !defined(HAVE_FTRUNCATE) */
 116         fflush(b->ufd);
 117         rc = ftruncate(fileno(b->ufd), loc);
 118         FSEEK(bf,loc,SEEK_SET);
 119 #endif /* !defined(HAVE_FTRUNCATE) */
 120         if (rc)
 121                 err(a->aerr,111,"endfile");
 122         return 0;
 123         }