summaryrefslogtreecommitdiffstats
path: root/src/libs/libgroff/tmpfile.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/libs/libgroff/tmpfile.cpp')
-rw-r--r--src/libs/libgroff/tmpfile.cpp188
1 files changed, 188 insertions, 0 deletions
diff --git a/src/libs/libgroff/tmpfile.cpp b/src/libs/libgroff/tmpfile.cpp
new file mode 100644
index 0000000..5e807ae
--- /dev/null
+++ b/src/libs/libgroff/tmpfile.cpp
@@ -0,0 +1,188 @@
+// -*- C++ -*-
+/* Copyright (C) 1989-2020 Free Software Foundation, Inc.
+ Written by James Clark (jjc@jclark.com)
+
+This file is part of groff.
+
+groff is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+groff is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#include "lib.h"
+
+#include <errno.h>
+#include <stdlib.h>
+
+#include "posix.h"
+#include "errarg.h"
+#include "error.h"
+#include "nonposix.h"
+
+// If this is set, create temporary files there
+#define GROFF_TMPDIR_ENVVAR "GROFF_TMPDIR"
+// otherwise if this is set, create temporary files there
+#define TMPDIR_ENVVAR "TMPDIR"
+// otherwise, on MS-DOS or MS-Windows ...
+#if defined(__MSDOS__) || defined(_WIN32)
+// if either of these is set, create temporary files there
+// (giving priority to WIN32_TMPDIR_ENVVAR)
+#define WIN32_TMPDIR_ENVVAR "TMP"
+#define MSDOS_TMPDIR_ENVVAR "TEMP"
+#endif
+// otherwise if P_tmpdir is defined, create temporary files there
+#ifdef P_tmpdir
+# define DEFAULT_TMPDIR P_tmpdir
+#else
+// otherwise create temporary files here.
+# define DEFAULT_TMPDIR "/tmp"
+#endif
+// Use this as the prefix for temporary filenames.
+#define TMPFILE_PREFIX_SHORT ""
+#define TMPFILE_PREFIX_LONG "groff"
+
+char *tmpfile_prefix;
+size_t tmpfile_prefix_len;
+int use_short_postfix = 0;
+
+struct temp_init {
+ temp_init();
+ ~temp_init();
+} _temp_init;
+
+temp_init::temp_init()
+{
+ // First, choose a location for creating temporary files...
+ const char *tem;
+ // using the first match for any of the environment specs in listed order.
+ if (
+ (tem = getenv(GROFF_TMPDIR_ENVVAR)) == 0
+ && (tem = getenv(TMPDIR_ENVVAR)) == 0
+#if defined(__MSDOS__) || defined(_WIN32)
+ // If we didn't find a match for either of the above
+ // (which are preferred, regardless of the host operating system),
+ // and we are hosted on either MS-Windows or MS-DOS,
+ // then try the Microsoft conventions.
+ && (tem = getenv(WIN32_TMPDIR_ENVVAR)) == 0
+ && (tem = getenv(MSDOS_TMPDIR_ENVVAR)) == 0
+#endif
+ )
+ // If we didn't find an environment spec fall back to this default.
+ tem = DEFAULT_TMPDIR;
+ size_t tem_len = strlen(tem);
+ const char *tem_end = tem + tem_len - 1;
+ int need_slash = (strchr(DIR_SEPS, *tem_end) == 0) ? 1 : 0;
+ char *tem2 = new char[tem_len + need_slash + 1];
+ strcpy(tem2, tem);
+ if (need_slash)
+ strcat(tem2, "/");
+ const char *tem3 = TMPFILE_PREFIX_LONG;
+ if (file_name_max(tem2) <= 14) {
+ tem3 = TMPFILE_PREFIX_SHORT;
+ use_short_postfix = 1;
+ }
+ tmpfile_prefix_len = tem_len + need_slash + strlen(tem3);
+ tmpfile_prefix = new char[tmpfile_prefix_len + 1];
+ strcpy(tmpfile_prefix, tem2);
+ strcat(tmpfile_prefix, tem3);
+ delete[] tem2;
+}
+
+temp_init::~temp_init()
+{
+ delete[] tmpfile_prefix;
+}
+
+/*
+ * Generate a temporary name template with a postfix
+ * immediately after the TMPFILE_PREFIX.
+ * It uses the groff preferences for a temporary directory.
+ * Note that no file name is either created or opened,
+ * only the *template* is returned.
+ */
+
+char *xtmptemplate(const char *postfix_long, const char *postfix_short)
+{
+ const char *postfix = use_short_postfix ? postfix_short : postfix_long;
+ int postlen = 0;
+ if (postfix)
+ postlen = strlen(postfix);
+ char *templ = new char[tmpfile_prefix_len + postlen + 6 + 1];
+ strcpy(templ, tmpfile_prefix);
+ if (postlen > 0)
+ strcat(templ, postfix);
+ strcat(templ, "XXXXXX");
+ return templ;
+}
+
+// The trick with unlinking the temporary file while it is still in
+// use is not portable, it will fail on MS-DOS and most MS-Windows
+// filesystems. So it cannot be used on non-Posix systems.
+// Instead, we maintain a list of files to be deleted on exit.
+// This should be portable to all platforms.
+
+struct xtmpfile_list {
+ char *fname;
+ xtmpfile_list *next;
+ xtmpfile_list(char *fn) : fname(fn), next(0) {}
+};
+
+xtmpfile_list *xtmpfiles_to_delete = 0;
+
+struct xtmpfile_list_init {
+ ~xtmpfile_list_init();
+} _xtmpfile_list_init;
+
+xtmpfile_list_init::~xtmpfile_list_init()
+{
+ xtmpfile_list *x = xtmpfiles_to_delete;
+ while (x != 0) {
+ if (unlink(x->fname) < 0)
+ error("cannot unlink '%1': %2", x->fname, strerror(errno));
+ xtmpfile_list *tmp = x;
+ x = x->next;
+ delete[] tmp->fname;
+ delete tmp;
+ }
+}
+
+static void add_tmp_file(const char *name)
+{
+ char *s = new char[strlen(name)+1];
+ strcpy(s, name);
+ xtmpfile_list *x = new xtmpfile_list(s);
+ x->next = xtmpfiles_to_delete;
+ xtmpfiles_to_delete = x;
+}
+
+// Open a temporary file and with fatal error on failure.
+
+FILE *xtmpfile(char **namep,
+ const char *postfix_long, const char *postfix_short,
+ int do_unlink)
+{
+ char *templ = xtmptemplate(postfix_long, postfix_short);
+ errno = 0;
+ int fd = mkstemp(templ);
+ if (fd < 0)
+ fatal("cannot create temporary file: %1", strerror(errno));
+ errno = 0;
+ FILE *fp = fdopen(fd, FOPEN_RWB); // many callers of xtmpfile use binary I/O
+ if (!fp)
+ fatal("fdopen: %1", strerror(errno));
+ if (do_unlink)
+ add_tmp_file(templ);
+ if (namep)
+ *namep = templ;
+ else
+ delete[] templ;
+ return fp;
+}