1 /* Utilities to execute a program in a subprocess (possibly linked by pipes
2    with other subprocesses), and wait for it.  DJGPP specialization.
3    Copyright (C) 1996-2018 Free Software Foundation, Inc.
4 
5 This file is part of the libiberty library.
6 Libiberty is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Library General Public
8 License as published by the Free Software Foundation; either
9 version 2 of the License, or (at your option) any later version.
10 
11 Libiberty is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14 Library General Public License for more details.
15 
16 You should have received a copy of the GNU Library General Public
17 License along with libiberty; see the file COPYING.LIB.  If not,
18 write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
19 Boston, MA 02110-1301, USA.  */
20 
21 #include "pex-common.h"
22 
23 #include <stdio.h>
24 #include <errno.h>
25 #ifdef NEED_DECLARATION_ERRNO
26 extern int errno;
27 #endif
28 #ifdef HAVE_STDLIB_H
29 #include <stdlib.h>
30 #endif
31 #include <string.h>
32 #include <fcntl.h>
33 #include <unistd.h>
34 #include <sys/stat.h>
35 #include <process.h>
36 
37 /* Use ECHILD if available, otherwise use EINVAL.  */
38 #ifdef ECHILD
39 #define PWAIT_ERROR ECHILD
40 #else
41 #define PWAIT_ERROR EINVAL
42 #endif
43 
44 static int pex_djgpp_open_read (struct pex_obj *, const char *, int);
45 static int pex_djgpp_open_write (struct pex_obj *, const char *, int, int);
46 static pid_t pex_djgpp_exec_child (struct pex_obj *, int, const char *,
47 				  char * const *, char * const *,
48 				  int, int, int, int,
49 				  const char **, int *);
50 static int pex_djgpp_close (struct pex_obj *, int);
51 static pid_t pex_djgpp_wait (struct pex_obj *, pid_t, int *, struct pex_time *,
52 			   int, const char **, int *);
53 
54 /* The list of functions we pass to the common routines.  */
55 
56 const struct pex_funcs funcs =
57 {
58   pex_djgpp_open_read,
59   pex_djgpp_open_write,
60   pex_djgpp_exec_child,
61   pex_djgpp_close,
62   pex_djgpp_wait,
63   NULL, /* pipe */
64   NULL, /* fdopenr */
65   NULL, /* fdopenw */
66   NULL  /* cleanup */
67 };
68 
69 /* Return a newly initialized pex_obj structure.  */
70 
71 struct pex_obj *
pex_init(int flags,const char * pname,const char * tempbase)72 pex_init (int flags, const char *pname, const char *tempbase)
73 {
74   /* DJGPP does not support pipes.  */
75   flags &= ~ PEX_USE_PIPES;
76   return pex_init_common (flags, pname, tempbase, &funcs);
77 }
78 
79 /* Open a file for reading.  */
80 
81 static int
pex_djgpp_open_read(struct pex_obj * obj ATTRIBUTE_UNUSED,const char * name,int binary)82 pex_djgpp_open_read (struct pex_obj *obj ATTRIBUTE_UNUSED,
83 		     const char *name, int binary)
84 {
85   return open (name, O_RDONLY | (binary ? O_BINARY : O_TEXT));
86 }
87 
88 /* Open a file for writing.  */
89 
90 static int
pex_djgpp_open_write(struct pex_obj * obj ATTRIBUTE_UNUSED,const char * name,int binary,int append)91 pex_djgpp_open_write (struct pex_obj *obj ATTRIBUTE_UNUSED,
92 		      const char *name, int binary, int append)
93 {
94   /* Note that we can't use O_EXCL here because gcc may have already
95      created the temporary file via make_temp_file.  */
96   if (append)
97     return -1;
98   return open (name,
99 	       (O_WRONLY | O_CREAT | O_TRUNC
100 		| (binary ? O_BINARY : O_TEXT)),
101 	       S_IRUSR | S_IWUSR);
102 }
103 
104 /* Close a file.  */
105 
106 static int
pex_djgpp_close(struct pex_obj * obj ATTRIBUTE_UNUSED,int fd)107 pex_djgpp_close (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd)
108 {
109   return close (fd);
110 }
111 
112 /* Execute a child.  */
113 
114 static pid_t
pex_djgpp_exec_child(struct pex_obj * obj,int flags,const char * executable,char * const * argv,char * const * env,int in,int out,int errdes,int toclose ATTRIBUTE_UNUSED,const char ** errmsg,int * err)115 pex_djgpp_exec_child (struct pex_obj *obj, int flags, const char *executable,
116 		      char * const * argv, char * const * env,
117                       int in, int out, int errdes,
118 		      int toclose ATTRIBUTE_UNUSED, const char **errmsg,
119 		      int *err)
120 {
121   int org_in, org_out, org_errdes;
122   int status;
123   int *statuses;
124 
125   org_in = -1;
126   org_out = -1;
127   org_errdes = -1;
128 
129   if (in != STDIN_FILE_NO)
130     {
131       org_in = dup (STDIN_FILE_NO);
132       if (org_in < 0)
133 	{
134 	  *err = errno;
135 	  *errmsg = "dup";
136 	  return (pid_t) -1;
137 	}
138       if (dup2 (in, STDIN_FILE_NO) < 0)
139 	{
140 	  *err = errno;
141 	  *errmsg = "dup2";
142 	  return (pid_t) -1;
143 	}
144       if (close (in) < 0)
145 	{
146 	  *err = errno;
147 	  *errmsg = "close";
148 	  return (pid_t) -1;
149 	}
150     }
151 
152   if (out != STDOUT_FILE_NO)
153     {
154       org_out = dup (STDOUT_FILE_NO);
155       if (org_out < 0)
156 	{
157 	  *err = errno;
158 	  *errmsg = "dup";
159 	  return (pid_t) -1;
160 	}
161       if (dup2 (out, STDOUT_FILE_NO) < 0)
162 	{
163 	  *err = errno;
164 	  *errmsg = "dup2";
165 	  return (pid_t) -1;
166 	}
167       if (close (out) < 0)
168 	{
169 	  *err = errno;
170 	  *errmsg = "close";
171 	  return (pid_t) -1;
172 	}
173     }
174 
175   if (errdes != STDERR_FILE_NO
176       || (flags & PEX_STDERR_TO_STDOUT) != 0)
177     {
178       org_errdes = dup (STDERR_FILE_NO);
179       if (org_errdes < 0)
180 	{
181 	  *err = errno;
182 	  *errmsg = "dup";
183 	  return (pid_t) -1;
184 	}
185       if (dup2 ((flags & PEX_STDERR_TO_STDOUT) != 0 ? STDOUT_FILE_NO : errdes,
186 		 STDERR_FILE_NO) < 0)
187 	{
188 	  *err = errno;
189 	  *errmsg = "dup2";
190 	  return (pid_t) -1;
191 	}
192       if (errdes != STDERR_FILE_NO)
193 	{
194 	  if (close (errdes) < 0)
195 	    {
196 	      *err = errno;
197 	      *errmsg = "close";
198 	      return (pid_t) -1;
199 	    }
200 	}
201     }
202 
203   if (env)
204     status = (((flags & PEX_SEARCH) != 0 ? spawnvpe : spawnve)
205 	      (P_WAIT, executable, argv, env));
206   else
207     status = (((flags & PEX_SEARCH) != 0 ? spawnvp : spawnv)
208   	      (P_WAIT, executable, argv));
209 
210   if (status == -1)
211     {
212       *err = errno;
213       *errmsg = ((flags & PEX_SEARCH) != 0) ? "spawnvp" : "spawnv";
214     }
215 
216   if (in != STDIN_FILE_NO)
217     {
218       if (dup2 (org_in, STDIN_FILE_NO) < 0)
219 	{
220 	  *err = errno;
221 	  *errmsg = "dup2";
222 	  return (pid_t) -1;
223 	}
224       if (close (org_in) < 0)
225 	{
226 	  *err = errno;
227 	  *errmsg = "close";
228 	  return (pid_t) -1;
229 	}
230     }
231 
232   if (out != STDOUT_FILE_NO)
233     {
234       if (dup2 (org_out, STDOUT_FILE_NO) < 0)
235 	{
236 	  *err = errno;
237 	  *errmsg = "dup2";
238 	  return (pid_t) -1;
239 	}
240       if (close (org_out) < 0)
241 	{
242 	  *err = errno;
243 	  *errmsg = "close";
244 	  return (pid_t) -1;
245 	}
246     }
247 
248   if (errdes != STDERR_FILE_NO
249       || (flags & PEX_STDERR_TO_STDOUT) != 0)
250     {
251       if (dup2 (org_errdes, STDERR_FILE_NO) < 0)
252 	{
253 	  *err = errno;
254 	  *errmsg = "dup2";
255 	  return (pid_t) -1;
256 	}
257       if (close (org_errdes) < 0)
258 	{
259 	  *err = errno;
260 	  *errmsg = "close";
261 	  return (pid_t) -1;
262 	}
263     }
264 
265   /* Save the exit status for later.  When we are called, obj->count
266      is the number of children which have executed before this
267      one.  */
268   statuses = (int *) obj->sysdep;
269   statuses = XRESIZEVEC (int, statuses, obj->count + 1);
270   statuses[obj->count] = status;
271   obj->sysdep = (void *) statuses;
272 
273   return (pid_t) obj->count;
274 }
275 
276 /* Wait for a child process to complete.  Actually the child process
277    has already completed, and we just need to return the exit
278    status.  */
279 
280 static pid_t
pex_djgpp_wait(struct pex_obj * obj,pid_t pid,int * status,struct pex_time * time,int done ATTRIBUTE_UNUSED,const char ** errmsg ATTRIBUTE_UNUSED,int * err ATTRIBUTE_UNUSED)281 pex_djgpp_wait (struct pex_obj *obj, pid_t pid, int *status,
282 		struct pex_time *time, int done ATTRIBUTE_UNUSED,
283 		const char **errmsg ATTRIBUTE_UNUSED,
284 		int *err ATTRIBUTE_UNUSED)
285 {
286   int *statuses;
287 
288   if (time != NULL)
289     memset (time, 0, sizeof *time);
290 
291   statuses = (int *) obj->sysdep;
292   *status = statuses[pid];
293 
294   return 0;
295 }
296