gcc/jit/jit-tempdir.cc

   1 /* Managing temporary directories and their content within libgccjit.so
   2    Copyright (C) 2014-2023 Free Software Foundation, Inc.
   3    Contributed by David Malcolm <dmalcolm@redhat.com>.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it
   8 under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 3, or (at your option)
  10 any later version.
  11
  12 GCC is distributed in the hope that it will be useful, but
  13 WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along 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
  39 static char *
  40 make_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
  74 gcc::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
  90 bool
  91 gcc::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
 126 gcc::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 }