pith/pipe.c

   1 /*
   2  * ========================================================================
   3  * Copyright 2013-2022 Eduardo Chappa
   4  * Copyright 2006 University of Washington
   5  *
   6  * Licensed under the Apache License, Version 2.0 (the "License");
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  *     http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  * ========================================================================
  13  */
  14
  15 #include "../pith/headers.h"
  16 #include "../pith/pipe.h"
  17 #include "../pith/status.h"
  18
  19
  20 /* Internal prototypes */
  21
  22
  23
  24 /*
  25  * pipe_* functions introduced so out.f, in.f don't need to be used
  26  * by whatever's setting up the pipe.
  27  * Should be similar on unix and windows, but since we're faking piping
  28  * in windows, closing the write pipe would signify that the child
  29  * process can start running.  This makes it possible for PIPE_WRITE
  30  * and PIPE_READ flags to be simultaneously set across all platforms.
  31  * Unix piping should eventually have NON_BLOCKING_IO stuff rolled up
  32  * into it.
  33  */
  34
  35 int
  36 pipe_putc(int c, PIPE_S *syspipe)
  37 {
  38     if(!syspipe || !syspipe->out.f)
  39       return -1;
  40
  41     return(fputc(c, syspipe->out.f));
  42 }
  43
  44 int
  45 pipe_puts(char *str, PIPE_S *syspipe)
  46 {
  47     if(!syspipe || !syspipe->out.f)
  48       return -1;
  49
  50     return(fputs(str, syspipe->out.f));
  51 }
  52
  53 char *
  54 pipe_gets(char *str, int size, PIPE_S *syspipe)
  55 {
  56     if(!syspipe || !syspipe->in.f)
  57       return NULL;
  58
  59     return(fgets(str, size, syspipe->in.f));
  60 }
  61
  62 int
  63 pipe_readc(unsigned char *c, PIPE_S *syspipe)
  64 {
  65     int rv = 0;
  66
  67     if(!syspipe || !syspipe->in.f)
  68       return -1;
  69
  70     do {
  71         errno = 0;
  72         clearerr(syspipe->in.f);
  73         rv = fread(c, sizeof(unsigned char), (size_t)1, syspipe->in.f);
  74     } while(!rv && ferror(syspipe->in.f) && errno == EINTR);
  75
  76     return(rv);
  77 }
  78
  79 int
  80 pipe_writec(int c, PIPE_S *syspipe)
  81 {
  82     unsigned char ch = (unsigned char)c;
  83     int rv = 0;
  84
  85     if(!syspipe || !syspipe->out.f)
  86       return -1;
  87
  88     do
  89       rv = fwrite(&ch, sizeof(unsigned char), (size_t)1, syspipe->out.f);
  90     while(!rv && ferror(syspipe->out.f) && errno == EINTR);
  91
  92     return(rv);
  93 }
  94
  95
  96 void
  97 pipe_report_error(char *errormsg)
  98 {
  99     q_status_message(SM_ORDER, 3, 3, errormsg);
 100 }