1 /* Copyright (C) 1994-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <hurd.h>
19 #include <stdio.h>
20 #include <fcntl.h>
21 #include <string.h>
22 
23 /* Read up to N chars into BUF from COOKIE.
24    Return how many chars were read, 0 for EOF or -1 for error.  */
25 static ssize_t
readio(void * cookie,char * buf,size_t n)26 readio (void *cookie, char *buf, size_t n)
27 {
28   mach_msg_type_number_t nread;
29   error_t err;
30   char *bufp = buf;
31 
32   nread = n;
33   if (err = __io_read ((io_t) cookie, &bufp, &nread, -1, n))
34     return __hurd_fail (err);
35 
36   if (bufp != buf)
37     {
38       memcpy (buf, bufp, nread);
39       __vm_deallocate (__mach_task_self (),
40 		       (vm_address_t) bufp, (vm_size_t) nread);
41     }
42 
43   return nread;
44 }
45 
46 /* Write up to N chars from BUF to COOKIE.
47    Return how many chars were written or -1 for error.  */
48 static ssize_t
writeio(void * cookie,const char * buf,size_t n)49 writeio (void *cookie, const char *buf, size_t n)
50 {
51   mach_msg_type_number_t wrote;
52   error_t err;
53 
54   if (err = __io_write ((io_t) cookie, buf, n, -1, &wrote))
55     return __hurd_fail (err);
56 
57   return wrote;
58 }
59 
60 /* Move COOKIE's file position *POS bytes, according to WHENCE.
61    The current file position is stored in *POS.
62    Returns zero if successful, nonzero if not.  */
63 static int
seekio(void * cookie,off64_t * pos,int whence)64 seekio (void *cookie,
65 	off64_t *pos,
66 	int whence)
67 {
68   error_t err = __io_seek ((file_t) cookie, *pos, whence, pos);
69   return err ? __hurd_fail (err) : 0;
70 }
71 
72 /* Close the file associated with COOKIE.
73    Return 0 for success or -1 for failure.  */
74 static int
closeio(void * cookie)75 closeio (void *cookie)
76 {
77   error_t error = __mach_port_deallocate (__mach_task_self (),
78 					  (mach_port_t) cookie);
79   if (error)
80     return __hurd_fail (error);
81   return 0;
82 }
83 
84 #include "../libio/libioP.h"
85 #define fopencookie _IO_fopencookie
86 static const cookie_io_functions_t funcsio =
87 { readio, writeio, seekio, closeio };
88 
89 
90 /* Open a stream on PORT.  MODE is as for fopen.  */
91 
92 FILE *
__fopenport(mach_port_t port,const char * mode)93 __fopenport (mach_port_t port, const char *mode)
94 {
95   int pflags;
96   int needflags;
97   error_t err;
98 
99   const char *m = mode;
100 
101   switch (*m++)
102     {
103     case 'r':
104       needflags = O_READ;
105       break;
106     case 'w':
107       needflags = O_WRITE;
108       break;
109     case 'a':
110       needflags = O_WRITE|O_APPEND;
111       break;
112     default:
113       return NULL;
114   }
115   if (m[0] == '+' || (m[0] == 'b' && m[1] == '+'))
116     needflags |= O_RDWR;
117 
118   /* Verify the PORT is valid allows the access MODE specifies.  */
119 
120   if (err = __io_get_openmodes (port, &pflags))
121     return __hurd_fail (err), NULL;
122 
123   /* Check the access mode.  */
124   if ((pflags & needflags) != needflags)
125     {
126       errno = EBADF;
127       return NULL;
128     }
129 
130   return fopencookie ((void *) port, mode, funcsio);
131 }
132 weak_alias (__fopenport, fopenport)
133