routines.c

Exuberant Ctags is a multilanguage reimplementation of the much-underused ctags(1) program and is i

				file.isExecutable = (boolean) ((status.st_mode &
					(S_IXUSR | S_IXGRP | S_IXOTH)) != 0);
				file.isSetuid = (boolean) ((status.st_mode & S_ISUID) != 0);
				file.size = status.st_size;
			}
		}
	}
	return &file;
}

extern boolean doesFileExist (const char *const fileName)
{
	fileStatus *status = eStat (fileName);
	return status->exists;
}

extern boolean isRecursiveLink (const char* const dirName)
{
	boolean result = FALSE;
	fileStatus *status = eStat (dirName);
	if (status->isSymbolicLink)
	{
		char* const path = absoluteFilename (dirName);
		while (path [strlen (path) - 1] == PATH_SEPARATOR)
			path [strlen (path) - 1] = '\0';
		while (! result  &&  strlen (path) > (size_t) 1)
		{
			char *const separator = strrchr (path, PATH_SEPARATOR);
			if (separator == NULL)
				break;
			else if (separator == path)  /* backed up to root directory */
				*(separator + 1) = '\0';
			else
				*separator = '\0';
			result = isSameFile (path, dirName);
		}
		eFree (path);
	}
	return result;
}

#ifndef HAVE_FGETPOS

extern int fgetpos (FILE *stream, fpos_t *pos)
{
	int result = 0;

	*pos = ftell (stream);
	if (*pos == -1L)
		result = -1;

	return result;
}

extern int fsetpos (FILE *stream, fpos_t const *pos)
{
	return fseek (stream, *pos, SEEK_SET);
}

#endif

/*
 *  Pathname manipulation (O/S dependent!!!)
 */

static boolean isPathSeparator (const int c)
{
	boolean result;
#if defined (MSDOS_STYLE_PATH) || defined (VMS)
	result = (boolean) (strchr (PathDelimiters, c) != NULL);
#else
	result = (boolean) (c == PATH_SEPARATOR);
#endif
	return result;
}

#if ! defined (HAVE_STAT_ST_INO)

static void canonicalizePath (char *const path __unused__)
{
#if defined (MSDOS_STYLE_PATH)
	char *p;
	for (p = path  ;  *p != '\0'  ;  ++p)
		if (isPathSeparator (*p)  &&  *p != ':')
			*p = PATH_SEPARATOR;
#endif
}

#endif

extern boolean isSameFile (const char *const name1, const char *const name2)
{
	boolean result = FALSE;
#if defined (HAVE_STAT_ST_INO)
	struct stat stat1, stat2;

	if (stat (name1, &stat1) == 0  &&  stat (name2, &stat2) == 0)
		result = (boolean) (stat1.st_ino == stat2.st_ino);
#else
	{
		char *const n1 = absoluteFilename (name1);
		char *const n2 = absoluteFilename (name2);
		canonicalizePath (n1);
		canonicalizePath (n2);
# if defined (CASE_INSENSITIVE_FILENAMES)
		result = (boolean) (strcasecmp (n1, n2) == 0);
#else
		result = (boolean) (strcmp (n1, n2) == 0);
#endif
		free (n1);
		free (n2);
	}
#endif
	return result;
}

extern const char *baseFilename (const char *const filePath)
{
#if defined (MSDOS_STYLE_PATH) || defined (VMS)
	const char *tail = NULL;
	unsigned int i;

	/*  Find whichever of the path delimiters is last.
	 */
	for (i = 0  ;  i < strlen (PathDelimiters)  ;  ++i)
	{
		const char *sep = strrchr (filePath, PathDelimiters [i]);

		if (sep > tail)
			tail = sep;
	}
#else
	const char *tail = strrchr (filePath, PATH_SEPARATOR);
#endif
	if (tail == NULL)
		tail = filePath;
	else
		++tail;  /* step past last delimiter */
#ifdef VAXC
	{
		/* remove version number from filename */
		char *p = strrchr ((char *) tail, ';');
		if (p != NULL)
			*p = '\0';
	}
#endif

	return tail;
}

extern const char *fileExtension (const char *const fileName)
{
	const char *extension;
	const char *pDelimiter = NULL;
	const char *const base = baseFilename (fileName);
#ifdef QDOS
	pDelimiter = strrchr (base, '_');
#endif
	if (pDelimiter == NULL)
	    pDelimiter = strrchr (base, '.');

	if (pDelimiter == NULL)
		extension = "";
	else
		extension = pDelimiter + 1;  /* skip to first char of extension */

	return extension;
}

extern boolean isAbsolutePath (const char *const path)
{
	boolean result = FALSE;
#if defined (MSDOS_STYLE_PATH)
	if (isPathSeparator (path [0]))
		result = TRUE;
	else if (isalpha (path [0])  &&  path [1] == ':')
	{
		if (isPathSeparator (path [2]))
			result = TRUE;
		else
			/*  We don't support non-absolute file names with a drive
			 *  letter, like `d:NAME' (it's too much hassle).
			 */
			error (FATAL,
				"%s: relative file names with drive letters not supported",
				path);
	}
#elif defined (VMS)
	result = (boolean) (strchr (path, ':') != NULL);
#else
	result = isPathSeparator (path [0]);
#endif
	return result;
}

extern vString *combinePathAndFile (
	const char *const path, const char *const file)
{
	vString *const filePath = vStringNew ();
#ifdef VMS
	const char *const directoryId = strstr (file, ".DIR;1");

	if (directoryId == NULL)
	{
		const char *const versionId = strchr (file, ';');

		vStringCopyS (filePath, path);
		if (versionId == NULL)
			vStringCatS (filePath, file);
		else
			vStringNCatS (filePath, file, versionId - file);
		vStringCopyToLower (filePath, filePath);
	}
	else
	{
		/*  File really is a directory; append it to the path.
		 *  Gotcha: doesn't work with logical names.
		 */
		vStringNCopyS (filePath, path, strlen (path) - 1);
		vStringPut (filePath, '.');
		vStringNCatS (filePath, file, directoryId - file);
		if (strchr (path, '[') != NULL)
			vStringPut (filePath, ']');
		else
			vStringPut (filePath, '>');
		vStringTerminate (filePath);
	}
#else
	const int lastChar = path [strlen (path) - 1];
	boolean terminated = isPathSeparator (lastChar);

	vStringCopyS (filePath, path);
	if (! terminated)
	{
		vStringPut (filePath, OUTPUT_PATH_SEPARATOR);
		vStringTerminate (filePath);
	}
	vStringCatS (filePath, file);
#endif

	return filePath;
}

/* Return a newly-allocated string whose contents concatenate those of
 * s1, s2, s3.
 * Routine adapted from Gnu etags.
 */
static char* concat (const char *s1, const char *s2, const char *s3)
{
  int len1 = strlen (s1), len2 = strlen (s2), len3 = strlen (s3);
  char *result = xMalloc (len1 + len2 + len3 + 1, char);

  strcpy (result, s1);
  strcpy (result + len1, s2);
  strcpy (result + len1 + len2, s3);
  result [len1 + len2 + len3] = '\0';

  return result;
}

/* Return a newly allocated string containing the absolute file name of FILE
 * given CWD (which should end with a slash).
 * Routine adapted from Gnu etags.
 */
extern char* absoluteFilename (const char *file)
{
	char *slashp, *cp;
	char *res = NULL;
	if (isAbsolutePath (file))
	{
#ifdef MSDOS_STYLE_PATH
		if (file [1] == ':')
			res = eStrdup (file);
		else
		{
			char drive [3];
			sprintf (drive, "%c:", currentdrive ());
			res = concat (drive, file, "");
		}
#else
		res = eStrdup (file);
#endif
	}
	else
		res = concat (CurrentDirectory, file, "");

	/* Delete the "/dirname/.." and "/." substrings. */
	slashp = strchr (res, PATH_SEPARATOR);
	while (slashp != NULL  &&  slashp [0] != '\0')
	{
		if (slashp[1] == '.')
		{
			if (slashp [2] == '.' &&
				(slashp [3] == PATH_SEPARATOR || slashp [3] == '\0'))
			{
				cp = slashp;
				do
					cp--;
				while (cp >= res  &&  ! isAbsolutePath (cp));
				if (cp < res)
					cp = slashp;/* the absolute name begins with "/.." */
#ifdef MSDOS_STYLE_PATH
				/* Under MSDOS and NT we get `d:/NAME' as absolute file name,
				 * so the luser could say `d:/../NAME'. We silently treat this
				 * as `d:/NAME'.
				 */
				else if (cp [0] != PATH_SEPARATOR)
					cp = slashp;
#endif
				strcpy (cp, slashp + 3);
				slashp = cp;
				continue;
			}
			else if (slashp [2] == PATH_SEPARATOR  ||  slashp [2] == '\0')
			{
				strcpy (slashp, slashp + 2);
				continue;
			}
		}
		slashp = strchr (slashp + 1, PATH_SEPARATOR);
	}

	if (res [0] == '\0')
		return eStrdup ("/");
	else
	{
#ifdef MSDOS_STYLE_PATH
		/* Canonicalize drive letter case. */
		if (res [1] == ':'  &&  islower (res [0]))
			res [0] = toupper (res [0]);
#endif

		return res;
	}
}

/* Return a newly allocated string containing the absolute file name of dir
 * where `file' resides given `CurrentDirectory'.
 * Routine adapted from Gnu etags.
 */
extern char* absoluteDirname (char *file)
{
	char *slashp, *res;
	char save;
	slashp = strrchr (file, PATH_SEPARATOR);
	if (slashp == NULL)
		res = eStrdup (CurrentDirectory);
	else
	{
		save = slashp [1];
		slashp [1] = '\0';
		res = absoluteFilename (file);
		slashp [1] = save;
	}
	return res;
}

/* Return a newly allocated string containing the file name of FILE relative
 * to the absolute directory DIR (which should end with a slash).
 * Routine adapted from Gnu etags.
 */
extern char* relativeFilename (const char *file, const char *dir)
{
	const char *fp, *dp;
	char *absdir, *res;
	int i;

	/* Find the common root of file and dir (with a trailing slash). */
	absdir = absoluteFilename (file);
	fp = absdir;
	dp = dir;
	while (*fp++ == *dp++)
		continue;
	fp--;
	dp--;  /* back to the first differing char */
	do
	{  /* look at the equal chars until path sep */
		if (fp == absdir)
			return absdir;  /* first char differs, give up */
		fp--;
		dp--;
	} while (*fp != PATH_SEPARATOR);

	/* Build a sequence of "../" strings for the resulting relative file name.
	 */
	i = 0;
	while ((dp = strchr (dp + 1, PATH_SEPARATOR)) != NULL)
		i += 1;
	res = xMalloc (3 * i + strlen (fp + 1) + 1, char);
	res [0] = '\0';
	while (i-- > 0)
		strcat (res, "../");

	/* Add the file name relative to the common root of file and dir. */
	strcat (res, fp + 1);
	free (absdir);

	return res;
}

extern FILE *tempFile (const char *const mode, char **const pName)
{
	char *name;
	FILE *fp;
	int fd;
#if defined(HAVE_MKSTEMP)
	const char *const pattern = "tags.XXXXXX";
	const char *tmpdir = NULL;
	fileStatus *file = eStat (ExecutableProgram);
	if (! file->isSetuid)
		tmpdir = getenv ("TMPDIR");
	if (tmpdir == NULL)
		tmpdir = TMPDIR;
	name = xMalloc (strlen (tmpdir) + 1 + strlen (pattern) + 1, char);
	sprintf (name, "%s%c%s", tmpdir, OUTPUT_PATH_SEPARATOR, pattern);
	fd = mkstemp (name);
#elif defined(HAVE_TEMPNAM)
	name = tempnam (TMPDIR, "tags");
	if (name == NULL)
		error (FATAL | PERROR, "cannot allocate temporary file name");
	fd = open (name, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
#else
	name = xMalloc (L_tmpnam, char);
	if (tmpnam (name) != name)
		error (FATAL | PERROR, "cannot assign temporary file name");
	fd = open (name, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
#endif
	if (fd == -1)
		error (FATAL | PERROR, "cannot open temporary file");
	fp = fdopen (fd, mode);
	if (fp == NULL)
		error (FATAL | PERROR, "cannot open temporary file");
	DebugStatement (
		debugPrintf (DEBUG_STATUS, "opened temporary file %s\n", name); )
	Assert (*pName == NULL);
	*pName = name;
	return fp;
}

/* vi:set tabstop=4 shiftwidth=4: */