font: Generate PDFs with correct font names

Escape PostScript names of loaded fonts. These can not
contain white spaces and delimiter characters when saving
them to a PostScript file or a PDF file.

1 files changed, 40 insertions, 0 deletions

diff --git a/src/cairo-scaled-font-subsets.c b/src/cairo-scaled-font-subsets.c
index e78e0c283..212176183 100644
--- a/src/cairo-scaled-font-subsets.c
+++ b/src/cairo-scaled-font-subsets.c
@@ -1256,4 +1256,44 @@ CLEANUP_HASH:
     return status;
 }
 
+cairo_int_status_t
+_cairo_escape_ps_name (char **ps_name)
+{
+    cairo_status_t status = CAIRO_STATUS_SUCCESS;
+
+    /* Ensure PS name is a valid PDF/PS name object. In PDF names are
+     * treated as UTF8 and non ASCII bytes, ' ', and '#' are encoded
+     * as '#' followed by 2 hex digits that encode the byte. By also
+     * encoding the characters in the reserved string we ensure the
+     * name is also PS compatible. */
+    if (*ps_name) {
+	static const char *reserved = "()<>[]{}/%#\\";
+	char buf[128]; /* max name length is 127 bytes */
+	char *src = *ps_name;
+	char *dst = buf;
+
+	while (*src && dst < buf + 127) {
+	    unsigned char c = *src;
+	    if (c < 0x21 || c > 0x7e || strchr (reserved, c)) {
+		if (dst + 4 > buf + 127)
+		    break;
+
+		snprintf (dst, 4, "#%02X", c);
+		src++;
+		dst += 3;
+	    } else {
+		*dst++ = *src++;
+	    }
+	}
+	*dst = 0;
+	free (*ps_name);
+	*ps_name = strdup (buf);
+	if (*ps_name == NULL) {
+	    status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
+	}
+    }
+
+    return status;
+}
+
 #endif /* CAIRO_HAS_FONT_SUBSET */