/* gtkbuilderparser.c * Copyright (C) 2019 Red Hat, * Alexander Larsson * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library 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 * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library. If not, see . */ #include "config.h" #include #include "gtkbuilderprivate.h" #include "gtkbuilder.h" #include "gtkbuildableprivate.h" /***************************************** Record a GMarkup parser call ***************************/ typedef enum { RECORD_TYPE_ELEMENT, RECORD_TYPE_END_ELEMENT, RECORD_TYPE_TEXT, } RecordTreeType; typedef struct RecordDataTree RecordDataTree; /* All strings are owned by the string table */ struct RecordDataTree { RecordDataTree *parent; RecordTreeType type; int n_attributes; const char *data; const char **attributes; const char **values; GList *children; }; typedef struct { char *string; int count; int offset; } RecordDataString; static RecordDataTree * record_data_tree_new (RecordDataTree *parent, RecordTreeType type, const char *data) { RecordDataTree *tree = g_slice_new0 (RecordDataTree); tree->parent = parent; tree->type = type; tree->data = data; if (parent) parent->children = g_list_prepend (parent->children, tree); return tree; } static void record_data_tree_free (RecordDataTree *tree) { g_list_free_full (tree->children, (GDestroyNotify)record_data_tree_free); g_free (tree->attributes); g_free (tree->values); g_slice_free (RecordDataTree, tree); } static void record_data_string_free (RecordDataString *s) { g_free (s->string); g_slice_free (RecordDataString, s); } static const char * record_data_string_lookup (GHashTable *strings, const char *str, gssize len) { char *copy = NULL; RecordDataString *s; if (len >= 0) { /* Ensure str is zero terminated */ copy = g_strndup (str, len); str = copy; } s = g_hash_table_lookup (strings, str); if (s) { g_free (copy); s->count++; return s->string; } s = g_slice_new (RecordDataString); s->string = copy ? copy : g_strdup (str); s->count = 1; g_hash_table_insert (strings, s->string, s); return s->string; } typedef struct { GHashTable *strings; RecordDataTree *root; RecordDataTree *current; } RecordData; static void record_start_element (GMarkupParseContext *context, const char *element_name, const char **names, const char **values, gpointer user_data, GError **error) { gsize n_attrs = g_strv_length ((char **)names); RecordData *data = user_data; RecordDataTree *child; int i; child = record_data_tree_new (data->current, RECORD_TYPE_ELEMENT, record_data_string_lookup (data->strings, element_name, -1)); data->current = child; child->n_attributes = n_attrs; child->attributes = g_new (const char *, n_attrs); child->values = g_new (const char *, n_attrs); for (i = 0; i < n_attrs; i++) { child->attributes[i] = record_data_string_lookup (data->strings, names[i], -1); child->values[i] = record_data_string_lookup (data->strings, values[i], -1); } } static void record_end_element (GMarkupParseContext *context, const char *element_name, gpointer user_data, GError **error) { RecordData *data = user_data; data->current = data->current->parent; } static void record_text (GMarkupParseContext *context, const char *text, gsize text_len, gpointer user_data, GError **error) { RecordData *data = user_data; record_data_tree_new (data->current, RECORD_TYPE_TEXT, record_data_string_lookup (data->strings, text, text_len)); } static const GMarkupParser record_parser = { record_start_element, record_end_element, record_text, NULL, // passthrough, not stored NULL, // error, fails immediately }; static int compare_string (gconstpointer _a, gconstpointer _b) { const RecordDataString *a = _a; const RecordDataString *b = _b; return b->count - a->count; } static void marshal_uint32 (GString *str, guint32 v) { /* We encode in a variable length format similar to utf8: v size byte 1 byte 2 byte 3 byte 4 byte 5 7 bit: 0xxxxxxx 14 bit: 10xxxxxx xxxxxxxx 21 bit: 110xxxxx xxxxxxxx xxxxxxxx 28 bit: 1110xxxx xxxxxxxx xxxxxxxx xxxxxxxx 32 bit: 11110000 xxxxxxxx xxxxxxxx xxxxxxxx xxxxxxx */ if (v < 128) { g_string_append_c (str, (guchar)v); } else if (v < (1<<14)) { g_string_append_c (str, (guchar)(v >> 8) | 0x80); g_string_append_c (str, (guchar)(v & 0xff)); } else if (v < (1<<21)) { g_string_append_c (str, (guchar)(v >> 16) | 0xc0); g_string_append_c (str, (guchar)((v >> 8) & 0xff)); g_string_append_c (str, (guchar)(v & 0xff)); } else if (v < (1<<28)) { g_string_append_c (str, (guchar)(v >> 24) | 0xe0); g_string_append_c (str, (guchar)((v >> 16) & 0xff)); g_string_append_c (str, (guchar)((v >> 8) & 0xff)); g_string_append_c (str, (guchar)(v & 0xff)); } else { g_string_append_c (str, 0xf0); g_string_append_c (str, (guchar)((v >> 24) & 0xff)); g_string_append_c (str, (guchar)((v >> 16) & 0xff)); g_string_append_c (str, (guchar)((v >> 8) & 0xff)); g_string_append_c (str, (guchar)(v & 0xff)); } } static void marshal_string (GString *marshaled, GHashTable *strings, const char *string) { RecordDataString *s; s = g_hash_table_lookup (strings, string); g_assert (s != NULL); marshal_uint32 (marshaled, s->offset); } static void marshal_tree (GString *marshaled, GHashTable *strings, RecordDataTree *tree) { GList *l; int i; /* Special case the root */ if (tree->parent == NULL) { for (l = g_list_last (tree->children); l != NULL; l = l->prev) marshal_tree (marshaled, strings, l->data); return; } switch (tree->type) { case RECORD_TYPE_ELEMENT: marshal_uint32 (marshaled, RECORD_TYPE_ELEMENT); marshal_string (marshaled, strings, tree->data); marshal_uint32 (marshaled, tree->n_attributes); for (i = 0; i < tree->n_attributes; i++) { marshal_string (marshaled, strings, tree->attributes[i]); marshal_string (marshaled, strings, tree->values[i]); } for (l = g_list_last (tree->children); l != NULL; l = l->prev) marshal_tree (marshaled, strings, l->data); marshal_uint32 (marshaled, RECORD_TYPE_END_ELEMENT); break; case RECORD_TYPE_TEXT: marshal_uint32 (marshaled, RECORD_TYPE_TEXT); marshal_string (marshaled, strings, tree->data); break; case RECORD_TYPE_END_ELEMENT: default: g_assert_not_reached (); } } /** * _gtk_buildable_parser_precompile: * @text: chunk of text to parse * @text_len: length of @text in bytes * * Converts the xml format typically used by GtkBuilder to a * binary form that is more efficient to parse. This is a custom * format that is only supported by GtkBuilder. * * returns: A `GBytes` with the precompiled data **/ GBytes * _gtk_buildable_parser_precompile (const char *text, gssize text_len, GError **error) { GMarkupParseContext *ctx; RecordData data = { 0 }; GList *string_table, *l; GString *marshaled; int offset; data.strings = g_hash_table_new_full (g_str_hash, g_str_equal, NULL, (GDestroyNotify)record_data_string_free); data.root = record_data_tree_new (NULL, RECORD_TYPE_ELEMENT, NULL); data.current = data.root; ctx = g_markup_parse_context_new (&record_parser, G_MARKUP_TREAT_CDATA_AS_TEXT, &data, NULL); if (!g_markup_parse_context_parse (ctx, text, text_len, error)) { record_data_tree_free (data.root); g_hash_table_destroy (data.strings); g_markup_parse_context_free (ctx); return NULL; } g_markup_parse_context_free (ctx); string_table = g_hash_table_get_values (data.strings); string_table = g_list_sort (string_table, compare_string); offset = 0; for (l = string_table; l != NULL; l = l->next) { RecordDataString *s = l->data; s->offset = offset; offset += strlen (s->string) + 1; } marshaled = g_string_new (""); /* Magic marker */ g_string_append_len (marshaled, "GBU\0", 4); marshal_uint32 (marshaled, offset); for (l = string_table; l != NULL; l = l->next) { RecordDataString *s = l->data; g_string_append_len (marshaled, s->string, strlen (s->string) + 1); } g_list_free (string_table); marshal_tree (marshaled, data.strings, data.root); record_data_tree_free (data.root); g_hash_table_destroy (data.strings); return g_string_free_to_bytes (marshaled); } /***************************************** Replay GMarkup parser callbacks ***************************/ static guint32 demarshal_uint32 (const char **tree) { const guchar *p = (const guchar *)*tree; guchar c = *p; /* see marshal_uint32 for format */ if (c < 128) /* 7 bit */ { *tree += 1; return c; } else if ((c & 0xc0) == 0x80) /* 14 bit */ { *tree += 2; return (c & 0x3f) << 8 | p[1]; } else if ((c & 0xe0) == 0xc0) /* 21 bit */ { *tree += 3; return (c & 0x1f) << 16 | p[1] << 8 | p[2]; } else if ((c & 0xf0) == 0xe0) /* 28 bit */ { *tree += 4; return (c & 0xf) << 24 | p[1] << 16 | p[2] << 8 | p[3]; } else { *tree += 5; return p[1] << 24 | p[2] << 16 | p[3] << 8 | p[4]; } } static const char * demarshal_string (const char **tree, const char *strings) { guint32 offset = demarshal_uint32 (tree); return strings + offset; } static void propagate_error (GtkBuildableParseContext *context, GError **dest, GError *src) { (*context->internal_callbacks->error) (NULL, src, context); g_propagate_error (dest, src); } static gboolean replay_start_element (GtkBuildableParseContext *context, const char **tree, const char *strings, GError **error) { const char *element_name; guint32 i, n_attrs; const char **attr_names; const char **attr_values; GError *tmp_error = NULL; element_name = demarshal_string (tree, strings); n_attrs = demarshal_uint32 (tree); attr_names = g_newa (const char *, n_attrs + 1); attr_values = g_newa (const char *, n_attrs + 1); for (i = 0; i < n_attrs; i++) { attr_names[i] = demarshal_string (tree, strings); attr_values[i] = demarshal_string (tree, strings); } attr_names[i] = NULL; attr_values[i] = NULL; (* context->internal_callbacks->start_element) (NULL, element_name, attr_names, attr_values, context, &tmp_error); if (tmp_error) { propagate_error (context, error, tmp_error); return FALSE; } return TRUE; } static gboolean replay_end_element (GtkBuildableParseContext *context, const char **tree, const char *strings, GError **error) { GError *tmp_error = NULL; (* context->internal_callbacks->end_element) (NULL, gtk_buildable_parse_context_get_element (context), context, &tmp_error); if (tmp_error) { propagate_error (context, error, tmp_error); return FALSE; } return TRUE; } static gboolean replay_text (GtkBuildableParseContext *context, const char **tree, const char *strings, GError **error) { const char *text; GError *tmp_error = NULL; text = demarshal_string (tree, strings); (*context->internal_callbacks->text) (NULL, text, strlen (text), context, &tmp_error); if (tmp_error) { propagate_error (context, error, tmp_error); return FALSE; } return TRUE; } gboolean _gtk_buildable_parser_is_precompiled (const char *data, gssize data_len) { return data_len > 4 && data[0] == 'G' && data[1] == 'B' && data[2] == 'U' && data[3] == 0; } gboolean _gtk_buildable_parser_replay_precompiled (GtkBuildableParseContext *context, const char *data, gssize data_len, GError **error) { const char *data_end = data + data_len; guint32 type, len; const char *strings; const char *tree; data = data + 4; /* Skip header */ len = demarshal_uint32 (&data); strings = data; data = data + len; tree = data; while (tree < data_end) { gboolean res; type = demarshal_uint32 (&tree); switch (type) { case RECORD_TYPE_ELEMENT: res = replay_start_element (context, &tree, strings, error); break; case RECORD_TYPE_END_ELEMENT: res = replay_end_element (context, &tree, strings, error); break; case RECORD_TYPE_TEXT: res = replay_text (context, &tree, strings, error); break; default: g_assert_not_reached (); } if (!res) return FALSE; } return TRUE; }