1/* Managing temporary directories and their content within libgccjit.so
2   Copyright (C) 2014-2022 Free Software Foundation, Inc.
3   Contributed by David Malcolm <dmalcolm@redhat.com>.
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify it
8under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 3, or (at your option)
10any later version.
11
12GCC is distributed in the hope that it will be useful, but
13WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING3.  If not see
19<http://www.gnu.org/licenses/>.  */
20
21#include "config.h"
22#include "system.h"
23#include "coretypes.h"
24
25#include "jit-tempdir.h"
26
27#ifdef _WIN32
28#include "jit-w32.h"
29#endif
30
31#ifndef _WIN32
32/* Construct a tempdir path template suitable for use by mkdtemp
33   e.g. "/tmp/libgccjit-XXXXXX", but respecting the rules in
34   libiberty's choose_tempdir rather than hardcoding "/tmp/".
35
36   The memory is allocated using malloc and must be freed.
37   Aborts the process if allocation fails. */
38
39static char *
40make_tempdir_path_template ()
41{
42  const char *tmpdir_buf;
43  size_t tmpdir_len;
44  const char *file_template_buf;
45  size_t file_template_len;
46  char *result;
47
48  /* The result of choose_tmpdir is a cached buffer within libiberty, so
49     we must *not* free it.  */
50  tmpdir_buf = choose_tmpdir ();
51
52  /* choose_tmpdir aborts on malloc failure.  */
53  gcc_assert (tmpdir_buf);
54
55  tmpdir_len = strlen (tmpdir_buf);
56  /* tmpdir_buf should now have a dir separator as the final byte.  */
57  gcc_assert (tmpdir_len > 0);
58  gcc_assert (tmpdir_buf[tmpdir_len - 1] == DIR_SEPARATOR);
59
60  file_template_buf = "libgccjit-XXXXXX";
61  file_template_len = strlen (file_template_buf);
62
63  result = XNEWVEC (char, tmpdir_len + file_template_len + 1);
64  strcpy (result, tmpdir_buf);
65  strcpy (result + tmpdir_len, file_template_buf);
66
67  return result;
68}
69#endif
70
71/* The constructor for the jit::tempdir object.
72   The real work is done by the jit::tempdir::create method.  */
73
74gcc::jit::tempdir::tempdir (logger *logger, int keep_intermediates)
75  : log_user (logger),
76    m_keep_intermediates (keep_intermediates),
77    m_path_template (NULL),
78    m_path_tempdir (NULL),
79    m_path_c_file (NULL),
80    m_path_s_file (NULL),
81    m_path_so_file (NULL)
82{
83  JIT_LOG_SCOPE (get_logger ());
84}
85
86/* Do the real work of creating the on-disk tempdir.
87   We do this here, rather than in the jit::tempdir constructor
88   so that we can handle failure without needing exceptions.  */
89
90bool
91gcc::jit::tempdir::create ()
92{
93  JIT_LOG_SCOPE (get_logger ());
94
95#ifdef _WIN32
96  m_path_tempdir = win_mkdtemp ();
97#else
98  m_path_template = make_tempdir_path_template ();
99  if (!m_path_template)
100    return false;
101
102  log ("m_path_template: %s", m_path_template);
103
104  /* Create tempdir using mkdtemp.  This is created with 0700 perms and
105     is unique.  Hence no other (non-root) users should have access to
106     the paths within it.  */
107  m_path_tempdir = mkdtemp (m_path_template);
108#endif
109
110  if (!m_path_tempdir)
111    return false;
112  log ("m_path_tempdir: %s", m_path_tempdir);
113
114  m_path_c_file = concat (m_path_tempdir, "/fake.c", NULL);
115  m_path_s_file = concat (m_path_tempdir, "/fake.s", NULL);
116  m_path_so_file = concat (m_path_tempdir, "/fake.so", NULL);
117
118  /* Success.  */
119  return true;
120}
121
122/* The destructor for the jit::tempdir object, which
123   cleans up the filesystem directory and its contents
124   (unless keep_intermediates was set).  */
125
126gcc::jit::tempdir::~tempdir ()
127{
128  JIT_LOG_SCOPE (get_logger ());
129
130  if (m_keep_intermediates)
131    fprintf (stderr, "intermediate files written to %s\n", m_path_tempdir);
132  else
133    {
134      /* Clean up .s/.so.  */
135      if (m_path_s_file)
136	{
137	  log ("unlinking .s file: %s", m_path_s_file);
138	  unlink (m_path_s_file);
139	}
140      if (m_path_so_file)
141	{
142	  log ("unlinking .so file: %s", m_path_so_file);
143	  unlink (m_path_so_file);
144	}
145
146      /* Clean up any other tempfiles.  */
147      int i;
148      char *tempfile;
149      FOR_EACH_VEC_ELT (m_tempfiles, i, tempfile)
150	{
151	  log ("unlinking tempfile: %s", tempfile);
152	  unlink (tempfile);
153	}
154
155      /* The tempdir should now be empty; remove it.  */
156      if (m_path_tempdir)
157	{
158	  log ("removing tempdir: %s", m_path_tempdir);
159	  rmdir (m_path_tempdir);
160	}
161    }
162
163  free (m_path_template);
164  /* m_path_tempdir aliases m_path_template, or is NULL, so don't
165     attempt to free it .  */
166  free (m_path_c_file);
167  free (m_path_s_file);
168  free (m_path_so_file);
169
170  int i;
171  char *tempfile;
172  FOR_EACH_VEC_ELT (m_tempfiles, i, tempfile)
173    free (tempfile);
174}
175