Implement HTML entity decoding in one function
authorRicardo Mones <ricardo@mones.org>
Mon, 6 Nov 2017 22:41:27 +0000 (23:41 +0100)
committerRicardo Mones <ricardo@mones.org>
Wed, 15 Nov 2017 19:35:48 +0000 (20:35 +0100)
Content of symbols table remixed from existing html.c and
rssyl/strutils.c tables.

src/Makefile.am
src/entity.c [new file with mode: 0644]
src/entity.h [new file with mode: 0644]

index 1db2b0d..d4eafbc 100644 (file)
@@ -142,6 +142,7 @@ claws_mail_SOURCES = \
        displayheader.c \
        edittags.c \
        enriched.c \
+       entity.c \
        export.c \
         file_checker.c \
        filtering.c \
@@ -260,6 +261,7 @@ claws_mailinclude_HEADERS = \
        displayheader.h \
        edittags.h \
        enriched.h \
+       entity.h \
        export.h \
        filtering.h \
        folder.h \
diff --git a/src/entity.c b/src/entity.c
new file mode 100644 (file)
index 0000000..cc72291
--- /dev/null
@@ -0,0 +1,255 @@
+/*
+ * Claws Mail -- a GTK+ based, lightweight, and fast e-mail client
+ * Copyright (C) 2017 Ricardo Mones and the Claws Mail team
+ *
+ * This program 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.
+ *
+ * This program 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/>.
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#include "claws-features.h"
+#endif
+
+#include "defs.h"
+#include "utils.h"
+#include "entity.h"
+
+#define ENTITY_MAX_LEN 8
+#define DECODED_MAX_LEN 6
+
+static GHashTable *symbol_table = NULL;
+
+typedef struct _EntitySymbol EntitySymbol;
+
+struct _EntitySymbol
+{
+       gchar *const key;
+       gchar *const value;
+};
+
+static EntitySymbol symbolic_entities[] = {
+       /* in alphabetical order with upper-case version first */
+       {"Aacute", "\303\201"},
+       {"aacute", "\303\241"},
+       {"Acirc", "\303\202"},
+       {"acirc", "\303\242"},
+       {"acute", "\302\264"},
+       {"AElig", "\303\206"},
+       {"aelig", "\303\246"},
+       {"Agrave", "\303\200"},
+       {"agrave", "\303\240"},
+       {"amp", "&" },
+       {"apos", "'" },
+       {"Aring", "\303\205"},
+       {"aring", "\303\245"},
+       {"Atilde", "\303\203"},
+       {"atilde", "\303\243"},
+       {"Auml", "\303\204"},
+       {"auml", "\303\244"},
+       {"bdquo", "\342\200\236"},
+       {"brvbar", "\302\246"},
+       {"bull", "\342\200\242"},
+       {"Ccedil", "\303\207"},
+       {"ccedil", "\303\247"},
+       {"cedil", "\302\270"},
+       {"cent", "\302\242"},
+       {"circ", "\313\206"},
+       {"copy", "©" },
+       {"curren", "\302\244"},
+       {"dagger", "\342\200\240"},
+       {"Dagger", "\342\200\241"},
+       {"deg", "\302\260"},
+       {"divide", "\303\267"},
+       {"Eacute", "\303\211"},
+       {"eacute", "\303\251"},
+       {"Ecirc", "\303\212"},
+       {"ecirc", "\303\252"},
+       {"Egrave", "\303\210"},
+       {"egrave", "\303\250"},
+       {"emsp", "\342\200\203"},
+       {"ensp", "\342\200\202"},
+       {"ETH", "\303\220"},
+       {"eth", "\303\260"},
+       {"Euml", "\303\213"},
+       {"euml", "\303\253"},
+       {"euro", "€" },
+       {"frac12", "\302\275"},
+       {"frac14", "\302\274"},
+       {"frac34", "\302\276"},
+       {"gt", ">" },
+       {"hellip", "…" },
+       {"Iacute", "\303\215"},
+       {"iacute", "\303\255"},
+       {"Icirc", "\303\216"},
+       {"icirc", "\303\256"},
+       {"iexcl", "\302\241"},
+       {"Igrave", "\303\214"},
+       {"igrave", "\303\254"},
+       {"iquest", "\302\277"},
+       {"Iuml", "\303\217"},
+       {"iuml", "\303\257"},
+       {"laquo", "\302\253"},
+       {"ldquo",  "“" },
+       {"lsaquo", "\342\200\271"},
+       {"lsquo",  "‘" },
+       {"lt", "<" },
+       {"macr", "\302\257"},
+       {"mdash", "—" },
+       {"micro", "\302\265"},
+       {"middot", "\302\267"},
+       {"nbsp", " " },
+       {"ndash", "\342\200\223"},
+       {"not", "\302\254"},
+       {"Ntilde", "\303\221"},
+       {"ntilde", "\303\261"},
+       {"Oacute", "\303\223"},
+       {"oacute", "\303\263"},
+       {"Ocirc", "\303\224"},
+       {"ocirc", "\303\264"},
+       {"OElig", "\305\222"},
+       {"oelig", "\305\223"},
+       {"Ograve", "\303\222"},
+       {"ograve", "\303\262"},
+       {"ordf", "\302\252"},
+       {"ordm", "\302\272"},
+       {"Oslash", "\303\230"},
+       {"oslash", "\303\270"},
+       {"Otilde", "\303\225"},
+       {"otilde", "\303\265"},
+       {"Ouml", "\303\226"},
+       {"ouml", "\303\266"},
+       {"para", "\302\266"},
+       {"permil", "\342\200\260"},
+       {"plusmn", "\302\261"},
+       {"pound", "\302\243"},
+       {"quot", "\"" },
+       {"raquo", "\302\273"},
+       {"rdquo",  "”" },
+       {"reg", "®" },
+       {"rsaquo", "\342\200\272"},
+       {"rsquo",  "’" },
+       {"sbquo", "\342\200\232"},
+       {"Scaron", "\305\240"},
+       {"scaron", "\305\241"},
+       {"sect", "\302\247"},
+       {"shy", "\302\255"},
+       {"squot", "\47"},
+       {"sup1", "\302\271"},
+       {"sup2", "\302\262"},
+       {"sup3", "\302\263"},
+       {"szlig", "\303\237"},
+       {"thinsp", "\342\200\211"},
+       {"THORN", "\303\236"},
+       {"thorn", "\303\276"},
+       {"tilde", "\313\234"},
+       {"times", "\303\227"},
+       {"trade", "™" },
+       {"Uacute", "\303\232"},
+       {"uacute", "\303\272"},
+       {"Ucirc", "\303\233"},
+       {"ucirc", "\303\273"},
+       {"Ugrave", "\303\231"},
+       {"ugrave", "\303\271"},
+       {"uml", "\302\250"},
+       {"Uuml", "\303\234"},
+       {"uuml", "\303\274"},
+       {"Yacute", "\303\235"},
+       {"yacute", "\303\275"},
+       {"yen", "\302\245"},
+       {"yuml", "\303\277"},
+       {"Yuml", "\305\270"},
+       {NULL, NULL}
+};
+
+static gchar* entity_extract_to_buffer(gchar *p, gchar b[])
+{
+       gint i = 0;
+
+       while (*p != '\0' && *p != ';' && i < ENTITY_MAX_LEN) {
+               b[i] = *p;
+               ++i, ++p;
+       }
+       if (*p != ';' || i == ENTITY_MAX_LEN)
+               return NULL;
+       b[i] = '\0';
+
+       return b;
+}
+
+static gchar *entity_decode_numeric(gchar *str)
+{
+       gchar b[ENTITY_MAX_LEN];
+       gchar *p = str, *res;
+       gboolean hex = FALSE;
+       gunichar c;
+
+       ++p;
+       if (*p == '\0')
+               return NULL;
+
+       if (*p == 'x') {
+               hex = TRUE;
+               ++p;
+               if (*p == '\0')
+                       return NULL;
+       }
+
+       if (entity_extract_to_buffer (p, b) == NULL)
+               return NULL;
+
+       c = g_ascii_strtoll (b, NULL, (hex? 16: 10));
+       res = g_malloc0 (DECODED_MAX_LEN + 1);
+       g_unichar_to_utf8 (c, res);
+
+       return res;
+}
+
+static gchar *entity_decode_symbol(gchar *str)
+{
+       gchar b[ENTITY_MAX_LEN];
+       gchar *decoded;
+
+       if (entity_extract_to_buffer (str, b) == NULL)
+               return NULL;
+
+       if (symbol_table == NULL) {
+               gint i;
+
+               symbol_table = g_hash_table_new (g_str_hash, g_str_equal);
+               for (i = 0; symbolic_entities[i].key != NULL; ++i) {
+                       g_hash_table_insert (symbol_table,
+                               symbolic_entities[i].key, symbolic_entities[i].value);
+               }
+               debug_print("initialized entities table with %d symbols\n", i);
+       }
+
+       decoded = g_hash_table_lookup (symbol_table, b);
+       if (decoded != NULL)
+               return g_strdup (decoded);
+
+       return NULL;
+}
+
+gchar *entity_decode(gchar *str)
+{
+       gchar *p = str;
+       if (p == NULL || *p != '&')
+               return NULL;
+       ++p;
+       if (*p == '\0')
+               return NULL;
+       if (*p == '#')
+               return entity_decode_numeric(p);
+       else
+               return entity_decode_symbol(p);
+}
diff --git a/src/entity.h b/src/entity.h
new file mode 100644 (file)
index 0000000..9e3e492
--- /dev/null
@@ -0,0 +1,33 @@
+/*
+ * Claws Mail -- a GTK+ based, lightweight, and fast e-mail client
+ * Copyright (C) 2017 Ricardo Mones and the Claws Mail team
+ *
+ * This program 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.
+ *
+ * This program 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/>.
+ */
+#ifndef __ENTITY_H__
+#define __ENTITY_H__
+
+#include <glib.h>
+
+/*
+ * Try to decode the HTML entity pointed by str, whose first element
+ * must be the '&' character.
+ *
+ * Returns a newly-allocated string with the decoded entity or NULL
+ * on failure to decode (like an unknown or invalid entity).
+ * Returned strings must be freed with g_free().
+ */
+gchar *entity_decode(gchar *str);
+
+#endif /* __ENTITY_H__ */