}
return NULL; /* unreached */
}
+
+/* Concatenate the NULL-terminated list of string arguments into
+ freshly allocated space. */
+
+char *
+concat_strings (const char *str0, ...)
+{
+ va_list args;
+ int saved_lengths[5]; /* inspired by Apache's apr_pstrcat */
+ char *ret, *p;
+
+ const char *next_str;
+ int total_length = 0;
+ int argcount;
+
+ /* Calculate the length of and allocate the resulting string. */
+
+ argcount = 0;
+ VA_START (args, str0);
+ for (next_str = str0; next_str != NULL; next_str = va_arg (args, char *))
+ {
+ int len = strlen (next_str);
+ if (argcount < countof (saved_lengths))
+ saved_lengths[argcount++] = len;
+ total_length += len;
+ }
+ va_end (args);
+ p = ret = xmalloc (total_length + 1);
+
+ /* Copy the strings into the allocated space. */
+
+ argcount = 0;
+ VA_START (args, str0);
+ for (next_str = str0; next_str != NULL; next_str = va_arg (args, char *))
+ {
+ int len;
+ if (argcount < countof (saved_lengths))
+ len = saved_lengths[argcount++];
+ else
+ len = strlen (next_str);
+ memcpy (p, next_str, len);
+ p += len;
+ }
+ va_end (args);
+ *p = '\0';
+
+ return ret;
+}
\f
/* Return pointer to a static char[] buffer in which zero-terminated
string-representation of TM (in form hh:mm:ss) is printed.
{
pid_t pid;
/* Whether we arrange our own version of opt.lfilename here. */
- int changedp = 0;
+ int logfile_changed = 0;
if (!opt.lfilename)
{
- opt.lfilename = unique_name (DEFAULT_LOGFILE, 0);
- changedp = 1;
+ /* We must create the file immediately to avoid either a race
+ condition (which arises from using unique_name and failing to
+ use fopen_excl) or lying to the user about the log file name
+ (which arises from using unique_name, printing the name, and
+ using fopen_excl later on.) */
+ FILE *new_log_fp = unique_create (DEFAULT_LOGFILE, 0, &opt.lfilename);
+ if (new_log_fp)
+ {
+ logfile_changed = 1;
+ fclose (new_log_fp);
+ }
}
pid = fork ();
if (pid < 0)
{
/* parent, no error */
printf (_("Continuing in background, pid %d.\n"), (int)pid);
- if (changedp)
+ if (logfile_changed)
printf (_("Output will be written to `%s'.\n"), opt.lfilename);
exit (0); /* #### should we use _exit()? */
}
exist at the point in time when the function was called.
Therefore, where security matters, don't rely that the file created
by this function exists until you open it with O_EXCL or
- something.
+ equivalent.
If ALLOW_PASSTHROUGH is 0, it always returns a freshly allocated
string. Otherwise, it may return FILE if the file doesn't exist
and return it. */
return unique_name_1 (file);
}
+
+/* Create a file based on NAME, except without overwriting an existing
+ file with that name. Providing O_EXCL is correctly implemented,
+ this function does not have the race condition associated with
+ opening the file returned by unique_name. */
+
+FILE *
+unique_create (const char *name, int binary, char **opened_name)
+{
+ /* unique file name, based on NAME */
+ char *uname = unique_name (name, 0);
+ FILE *fp;
+ while ((fp = fopen_excl (uname, binary)) == NULL && errno == EEXIST)
+ {
+ xfree (uname);
+ uname = unique_name (name, 0);
+ }
+ if (opened_name && fp != NULL)
+ {
+ if (fp)
+ *opened_name = uname;
+ else
+ {
+ *opened_name = NULL;
+ xfree (uname);
+ }
+ }
+ else
+ xfree (uname);
+ return fp;
+}
+
+/* Open the file for writing, with the addition that the file is
+ opened "exclusively". This means that, if the file already exists,
+ this function will *fail* and errno will be set to EEXIST. If
+ BINARY is set, the file will be opened in binary mode, equivalent
+ to fopen's "wb".
+
+ If opening the file fails for any reason, including the file having
+ previously existed, this function returns NULL and sets errno
+ appropriately. */
+
+FILE *
+fopen_excl (const char *fname, int binary)
+{
+ int fd;
+#ifdef O_EXCL
+ int flags = O_WRONLY | O_CREAT | O_EXCL;
+# ifdef O_BINARY
+ if (binary)
+ flags |= O_BINARY;
+# endif
+ fd = open (fname, flags, 0666);
+ if (fd < 0)
+ return NULL;
+ return fdopen (fd, binary ? "wb" : "w");
+#else /* not O_EXCL */
+ return fopen (fname, binary ? "wb" : "w");
+#endif /* not O_EXCL */
+}
\f
/* Create DIRECTORY. If some of the pathname components of DIRECTORY
are missing, create them first. In case any mkdir() call fails,
int
make_directory (const char *directory)
{
- int quit = 0;
- int i;
- int ret = 0;
+ int i, ret, quit = 0;
char *dir;
/* Make a copy of dir, to be able to write to it. Otherwise, the
{
int fd;
struct file_memory *fm;
- wgint size;
+ long size;
int inhibit_close = 0;
/* Some magic in the finest tradition of Perl and its kin: if FILE
# define C100000000000000000 100000000000000000LL
# define C1000000000000000000 1000000000000000000LL
# else
-# if defined(_MSC_VER) || defined(__WATCOM__)
-/* Otherwise, if __int64 is available (under Windows), use __int64
- constants. */
+# if defined(WINDOWS)
+/* Use __int64 constants under Windows. */
# define C10000000000 10000000000I64
# define C100000000000 100000000000I64
# define C1000000000000 1000000000000I64
# if SIZEOF_LONG_LONG >= SIZEOF_WGINT
# define SPRINTF_WGINT(buf, n) sprintf(buf, "%lld", (long long) (n))
# else
-# ifdef _MSC_VER
+# ifdef WINDOWS
# define SPRINTF_WGINT(buf, n) sprintf(buf, "%I64", (__int64) (n))
# endif
# endif
projects / wget / blobdiff