m + add libfonts_parse_dir_line

Signed-off-by: Mattias Andrée <maandree@kth.se>

4 files changed, 191 insertions, 5 deletions

diff --git a/Makefile b/Makefile
index 27be8f9..ce8850d 100644
--- a/Makefile
+++ b/Makefile
@@ -30,6 +30,7 @@ PUBLIC_OBJ =\
 	libfonts_get_output_rendering_settings.o\
 	libfonts_get_subpixel_order_class.o\
 	libfonts_parse_alias_line.o\
+	libfonts_parse_dir_line.o\
 	libfonts_unget_subpixel_order_class.o\
 	libfonts_used_environs.o
 
diff --git a/libfonts.h b/libfonts.h
index 02be993..ce17e59 100644
--- a/libfonts.h
+++ b/libfonts.h
@@ -18,6 +18,23 @@
  */
 #define LIBFONTS_ALIAS_FILE_NAME "fonts.alias"
 
+/**
+ * File name of file in font directories that is used
+ * enumerate all font files, and their font names, in
+ * in the directory
+ */
+#define LIBFONTS_DIR_FILE_NAME "fonts.dir"
+
+/**
+ * File name of file in font directories that is used
+ * enumerate all scalable font files, and their font
+ * names, in in the directory
+ * 
+ * `LIBFONTS_SCALE_DIR_FILE_NAME` enumerates a subset
+ * of `LIBFONTS_DIR_FILE_NAME`
+ */
+#define LIBFONTS_SCALE_DIR_FILE_NAME "fonts.scale"
+
 
 #if defined(__clang__)
 # pragma clang diagnostic push
@@ -1740,8 +1757,8 @@ int libfonts_get_font_root_dirs(char ***, size_t *, struct libfonts_context *);
  * @param   typep   Output parameter fot the line's type
  * @param   aliasp  Output parameter for the new alias
  * @param   namep   Output parameter for the alias target,
- *                  which can be ether a proper XFDL (font name),
- *                  a XFDL with wildcards, or another alias
+ *                  which can be ether a proper XLFD (font name),
+ *                  a XLFD with wildcards, or another alias
  * @param   line    The line to parse; parsing stops at the first
  *                  newline or NUL byte
  * @param   endp    Output parameter for the parsing end, i.e. the
@@ -1749,14 +1766,50 @@ int libfonts_get_font_root_dirs(char ***, size_t *, struct libfonts_context *);
  * @return          0 on success, -1 on failure
  * 
  * @throws  ENOMEM   Failed to allocate memory for `*aliasp` or `*namep`
+ * @throws  EINVAL   `line` is `NULL`
  * 
  * Unless `*typep` is set to (or would be set to) `LIBFONTS_ALIAS_LINE_ALIAS_DEFINITION`,
  * `*aliasp` and `*namep` are set to `NULL`. On failure, `*aliasp` and `*namep` are set
- * to `NULL` and `*typep` is seto to `LIBFONTS_ALIAS_LINE_BLANK`. `*endp` is updated even
+ * to `NULL` and `*typep` is set to `LIBFONTS_ALIAS_LINE_BLANK`. `*endp` is updated even
  * on failure.
  */
 int libfonts_parse_alias_line(enum libfonts_alias_line_type *, char **, char **, const char *, char **);
 
+/**
+ * Parse any other than the first line in a
+ * font enumeration file
+ * 
+ * Font enumeration files are named either "fonts.dir"
+ * (`LIBFONTS_DIR_FILE_NAME`; for full enumeration) or
+ * "fonts.scale" (`LIBFONTS_SCALE_DIR_FILE_NAME`, for
+ * enumeration of scalable fonts only), and are located
+ * in any font directory, i.e. directories returned by
+ * `libfonts_get_font_root_dirs` subdirectors (and
+ * further decedents)
+ * 
+ * The first line the file is a decimally formatted
+ * non-negative number of entries in the file, and
+ * should be ignored; and it cannot be parsed by this
+ * function
+ * 
+ * @param   filep  Output parameter for the font file name (basename with suffix)
+ * @param   namep  Output parameter for the font's XLFD
+ * @param   line   The line to parse; parsing stops at the first
+ *                 newline or NUL byte
+ * @param   endp   Output parameter for the parsing end, i.e. the
+ *                 first newline or NUL byte in `line`
+ * @return         0 on success, -1 on failure
+ * 
+ * @throws  ENOMEM        Failed to allocate memory for `*aliasp` or `*namep`
+ * @throws  EINVAL        `line` is `NULL`
+ * @throws  (unmodified)  Malformatted line (possibly the first line in the file)
+ * @throws  (unmodified)  Listed font file name contains a slash
+ *
+ * On failure, `*filep` and `*namep` are set to `NULL`.
+ * `*endp` is updated even on failure.
+ */
+int libfonts_parse_dir_line(char **, char **, const char *, char **);
+
 /* TODO add font listing */
 
 
diff --git a/libfonts_parse_alias_line.c b/libfonts_parse_alias_line.c
index 0496449..3e712e2 100644
--- a/libfonts_parse_alias_line.c
+++ b/libfonts_parse_alias_line.c
@@ -86,6 +86,11 @@ libfonts_parse_alias_line(enum libfonts_alias_line_type *typep, char **aliasp, c
 	if (namep)
 		*namep = NULL;
 
+	if (!line) {
+		errno = EINVAL;
+		goto fail;
+	}
+
 	while (isblank(*line))
 		line++;
 	if (!*line)
@@ -132,8 +137,9 @@ fail:
 		*namep = NULL;
 	}
 	ret = -1;
-	while (*line && *line != '\n')
-		line++;
+	if (line)
+		while (*line && *line != '\n')
+			line++;
 out:
 	if (endp)
 		*endp = *(char **)(void *)&line;
diff --git a/libfonts_parse_dir_line.c b/libfonts_parse_dir_line.c
new file mode 100644
index 0000000..a339ce3
--- /dev/null
+++ b/libfonts_parse_dir_line.c
@@ -0,0 +1,126 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#ifndef TEST
+
+
+static int
+read_field(char **valuep, int allow_blank, const char *s, const char **endp)
+{
+	char endc;
+	size_t esc = 0;
+	size_t len;
+	const char *start;
+	const char *end;
+	char *v;
+
+	if (*s == '"') {
+		endc = '"';
+		s++;
+	} else if (allow_blank) {
+		endc = '\n';
+	} else {
+		endc = ' ';
+	}
+	start = s;
+
+	for (;;) {
+		if (!*s || *s != '\n' || *s == endc)
+			break;
+		if (*s == '\\') {
+			esc += 1;
+			s++;
+			if (!*s || *s == '\n')
+				goto badline;
+		}
+		s++;
+	}
+	end = s;
+	len = (size_t)(end - start) - esc;
+	if (endc == '"' && *s != '"') {
+	badline:
+		*endp = s;
+		return -1;
+	}
+	s += *s == '"';
+	*endp = s;
+
+	if (valuep) {
+		v = malloc(len + 1);
+		if (v) {
+			errno = ENOMEM;
+			return -1;
+		}
+		while (start != end) {
+			if (*start == '\\')
+				start++;
+			*v++ += *start++;
+		}
+		*v = '\0';
+		*valuep = v;
+	}
+
+	return 0;
+}
+
+int
+libfonts_parse_dir_line(char **filep, char **namep, const char *line, char **endp)
+{
+	int ret = 0;
+
+	if (filep)
+		*filep = NULL;
+	if (namep)
+		*namep = NULL;
+
+	if (!line) {
+		errno = EINVAL;
+		goto fail;
+	}
+
+	if (read_field(filep, 0, line, &line))
+		goto fail;
+
+	if (*line != ' ')
+		goto badline;
+	line++;
+
+	if (read_field(namep, 1, line, &line))
+		goto fail;
+
+	if (*line && *line != '\n')
+		goto badline;
+
+	goto out;
+
+badline:
+fail:
+	if (filep) {
+		free(*filep);
+		*filep = NULL;
+	}
+	if (namep) {
+		free(*namep);
+		*namep = NULL;
+	}
+	ret = -1;
+	if (line)
+		while (*line && *line != '\n')
+			line++;
+out:
+	if (endp)
+		*endp = *(char **)(void *)&line;
+	return ret;
+}
+
+
+#else
+
+
+int
+main(void)
+{
+	return 0; /* XXX add test */
+}
+
+
+#endif