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-rw-r--r--src/3rdparty/libcroco/cr-input.c1181
1 files changed, 1181 insertions, 0 deletions
diff --git a/src/3rdparty/libcroco/cr-input.c b/src/3rdparty/libcroco/cr-input.c
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+++ b/src/3rdparty/libcroco/cr-input.c
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+/* -*- Mode: C; indent-tabs-mode: nil; c-basic-offset: 8-*- */
+
+/*
+ * This file is part of The Croco Library
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2.1 of the GNU Lesser General Public
+ * License as published by the Free Software Foundation.
+ *
+ * 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 Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+ * USA
+ *
+ * Author: Dodji Seketeli
+ * See COPYRIGHTS file for copyright information.
+ */
+
+#include "stdio.h"
+#include <string.h>
+#include "cr-input.h"
+#include "cr-enc-handler.h"
+
+/**
+ *@CRInput:
+ *
+ *The definition of the #CRInput class.
+ */
+
+/*******************
+ *Private type defs
+ *******************/
+
+/**
+ *The private attributes of
+ *the #CRInputPriv class.
+ */
+struct _CRInputPriv {
+ /*
+ *The input buffer
+ */
+ guchar *in_buf;
+ gulong in_buf_size;
+
+ gulong nb_bytes;
+
+ /*
+ *The index of the next byte
+ *to be read.
+ */
+ gulong next_byte_index;
+
+ /*
+ *The current line number
+ */
+ gulong line;
+
+ /*
+ *The current col number
+ */
+ gulong col;
+
+ gboolean end_of_line;
+ gboolean end_of_input;
+
+ /*
+ *the reference count of this
+ *instance.
+ */
+ guint ref_count;
+ gboolean free_in_buf;
+};
+
+#define PRIVATE(object) (object)->priv
+
+/***************************
+ *private constants
+ **************************/
+#define CR_INPUT_MEM_CHUNK_SIZE 1024 * 4
+
+static CRInput *cr_input_new_real (void);
+
+static CRInput *
+cr_input_new_real (void)
+{
+ CRInput *result = NULL;
+
+ result = g_try_malloc (sizeof (CRInput));
+ if (!result) {
+ cr_utils_trace_info ("Out of memory");
+ return NULL;
+ }
+ memset (result, 0, sizeof (CRInput));
+
+ PRIVATE (result) = g_try_malloc (sizeof (CRInputPriv));
+ if (!PRIVATE (result)) {
+ cr_utils_trace_info ("Out of memory");
+ g_free (result);
+ return NULL;
+ }
+ memset (PRIVATE (result), 0, sizeof (CRInputPriv));
+ PRIVATE (result)->free_in_buf = TRUE;
+ return result;
+}
+
+/****************
+ *Public methods
+ ***************/
+
+/**
+ * cr_input_new_from_buf:
+ *@a_buf: the memory buffer to create the input stream from.
+ *The #CRInput keeps this pointer so user should not free it !.
+ *@a_len: the size of the input buffer.
+ *@a_enc: the buffer's encoding.
+ *@a_free_buf: if set to TRUE, this a_buf will be freed
+ *at the destruction of this instance. If set to false, it is up
+ *to the caller to free it.
+ *
+ *Creates a new input stream from a memory buffer.
+ *Returns the newly built instance of #CRInput.
+ */
+CRInput *
+cr_input_new_from_buf (guchar * a_buf,
+ gulong a_len,
+ enum CREncoding a_enc,
+ gboolean a_free_buf)
+{
+ CRInput *result = NULL;
+ enum CRStatus status = CR_OK;
+ CREncHandler *enc_handler = NULL;
+ gulong len = a_len;
+
+ g_return_val_if_fail (a_buf, NULL);
+
+ result = cr_input_new_real ();
+ g_return_val_if_fail (result, NULL);
+
+ /*transform the encoding in utf8 */
+ if (a_enc != CR_UTF_8) {
+ enc_handler = cr_enc_handler_get_instance (a_enc);
+ if (!enc_handler) {
+ goto error;
+ }
+
+ status = cr_enc_handler_convert_input
+ (enc_handler, a_buf, &len,
+ &PRIVATE (result)->in_buf,
+ &PRIVATE (result)->in_buf_size);
+ if (status != CR_OK)
+ goto error;
+ PRIVATE (result)->free_in_buf = TRUE;
+ if (a_free_buf == TRUE && a_buf) {
+ g_free (a_buf) ;
+ a_buf = NULL ;
+ }
+ PRIVATE (result)->nb_bytes = PRIVATE (result)->in_buf_size;
+ } else {
+ PRIVATE (result)->in_buf = (guchar *) a_buf;
+ PRIVATE (result)->in_buf_size = a_len;
+ PRIVATE (result)->nb_bytes = a_len;
+ PRIVATE (result)->free_in_buf = a_free_buf;
+ }
+ PRIVATE (result)->line = 1;
+ PRIVATE (result)->col = 0;
+ return result;
+
+ error:
+ if (result) {
+ cr_input_destroy (result);
+ result = NULL;
+ }
+
+ return NULL;
+}
+
+/**
+ * cr_input_new_from_uri:
+ *@a_file_uri: the file to create *the input stream from.
+ *@a_enc: the encoding of the file *to create the input from.
+ *
+ *Creates a new input stream from
+ *a file.
+ *
+ *Returns the newly created input stream if
+ *this method could read the file and create it,
+ *NULL otherwise.
+ */
+
+CRInput *
+cr_input_new_from_uri (const gchar * a_file_uri, enum CREncoding a_enc)
+{
+ CRInput *result = NULL;
+ enum CRStatus status = CR_OK;
+ FILE *file_ptr = NULL;
+ guchar tmp_buf[CR_INPUT_MEM_CHUNK_SIZE] = { 0 };
+ gulong nb_read = 0,
+ len = 0;
+ gboolean loop = TRUE;
+ guchar *buf = NULL;
+
+ g_return_val_if_fail (a_file_uri, NULL);
+
+ file_ptr = fopen (a_file_uri, "r");
+
+ if (file_ptr == NULL) {
+
+#ifdef CR_DEBUG
+ cr_utils_trace_debug ("could not open file");
+#endif
+ g_warning ("Could not open file %s\n", a_file_uri);
+
+ return NULL;
+ }
+
+ /*load the file */
+ while (loop) {
+ nb_read = fread (tmp_buf, 1 /*read bytes */ ,
+ CR_INPUT_MEM_CHUNK_SIZE /*nb of bytes */ ,
+ file_ptr);
+
+ if (nb_read != CR_INPUT_MEM_CHUNK_SIZE) {
+ /*we read less chars than we wanted */
+ if (feof (file_ptr)) {
+ /*we reached eof */
+ loop = FALSE;
+ } else {
+ /*a pb occurred !! */
+ cr_utils_trace_debug ("an io error occurred");
+ status = CR_ERROR;
+ goto cleanup;
+ }
+ }
+
+ if (status == CR_OK) {
+ /*read went well */
+ buf = g_realloc (buf, len + CR_INPUT_MEM_CHUNK_SIZE);
+ memcpy (buf + len, tmp_buf, nb_read);
+ len += nb_read;
+ }
+ }
+
+ if (status == CR_OK) {
+ result = cr_input_new_from_buf (buf, len, a_enc, TRUE);
+ if (!result) {
+ goto cleanup;
+ }
+ /*
+ *we should free buf here because it's own by CRInput.
+ *(see the last parameter of cr_input_new_from_buf().
+ */
+ buf = NULL;
+ }
+
+ cleanup:
+ if (file_ptr) {
+ fclose (file_ptr);
+ file_ptr = NULL;
+ }
+
+ if (buf) {
+ g_free (buf);
+ buf = NULL;
+ }
+
+ return result;
+}
+
+/**
+ * cr_input_destroy:
+ *@a_this: the current instance of #CRInput.
+ *
+ *The destructor of the #CRInput class.
+ */
+void
+cr_input_destroy (CRInput * a_this)
+{
+ if (a_this == NULL)
+ return;
+
+ if (PRIVATE (a_this)) {
+ if (PRIVATE (a_this)->in_buf && PRIVATE (a_this)->free_in_buf) {
+ g_free (PRIVATE (a_this)->in_buf);
+ PRIVATE (a_this)->in_buf = NULL;
+ }
+
+ g_free (PRIVATE (a_this));
+ PRIVATE (a_this) = NULL;
+ }
+
+ g_free (a_this);
+}
+
+/**
+ * cr_input_ref:
+ *@a_this: the current instance of #CRInput.
+ *
+ *Increments the reference count of the current
+ *instance of #CRInput.
+ */
+void
+cr_input_ref (CRInput * a_this)
+{
+ g_return_if_fail (a_this && PRIVATE (a_this));
+
+ PRIVATE (a_this)->ref_count++;
+}
+
+/**
+ * cr_input_unref:
+ *@a_this: the current instance of #CRInput.
+ *
+ *Decrements the reference count of this instance
+ *of #CRInput. If the reference count goes down to
+ *zero, this instance is destroyed.
+ *
+ * Returns TRUE if the instance of #CRInput got destroyed, false otherwise.
+ */
+gboolean
+cr_input_unref (CRInput * a_this)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), FALSE);
+
+ if (PRIVATE (a_this)->ref_count) {
+ PRIVATE (a_this)->ref_count--;
+ }
+
+ if (PRIVATE (a_this)->ref_count == 0) {
+ cr_input_destroy (a_this);
+ return TRUE;
+ }
+ return FALSE;
+}
+
+/**
+ * cr_input_end_of_input:
+ *@a_this: the current instance of #CRInput.
+ *@a_end_of_input: out parameter. Is set to TRUE if
+ *the current instance has reached the end of its input buffer,
+ *FALSE otherwise.
+ *
+ *Tests whether the current instance of
+ *#CRInput has reached its input buffer.
+ *
+ * Returns CR_OK upon successful completion, an error code otherwise.
+ * Note that all the out parameters of this method are valid if
+ * and only if this method returns CR_OK.
+ */
+enum CRStatus
+cr_input_end_of_input (CRInput const * a_this, gboolean * a_end_of_input)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this)
+ && a_end_of_input, CR_BAD_PARAM_ERROR);
+
+ *a_end_of_input = (PRIVATE (a_this)->next_byte_index
+ >= PRIVATE (a_this)->in_buf_size) ? TRUE : FALSE;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_get_nb_bytes_left:
+ *@a_this: the current instance of #CRInput.
+ *
+ *Returns the number of bytes left in the input stream
+ *before the end, -1 in case of error.
+ */
+glong
+cr_input_get_nb_bytes_left (CRInput const * a_this)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), -1);
+ g_return_val_if_fail (PRIVATE (a_this)->nb_bytes
+ <= PRIVATE (a_this)->in_buf_size, -1);
+ g_return_val_if_fail (PRIVATE (a_this)->next_byte_index
+ <= PRIVATE (a_this)->nb_bytes, -1);
+
+ if (PRIVATE (a_this)->end_of_input)
+ return 0;
+
+ return PRIVATE (a_this)->nb_bytes - PRIVATE (a_this)->next_byte_index;
+}
+
+/**
+ * cr_input_read_byte:
+ *@a_this: the current instance of #CRInput.
+ *@a_byte: out parameter the returned byte.
+ *
+ *Gets the next byte of the input.
+ *Updates the state of the input so that
+ *the next invocation of this method returns
+ *the next coming byte.
+ *
+ *Returns CR_OK upon successful completion, an error code
+ *otherwise. All the out parameters of this method are valid if
+ *and only if this method returns CR_OK.
+ */
+enum CRStatus
+cr_input_read_byte (CRInput * a_this, guchar * a_byte)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this)
+ && a_byte, CR_BAD_PARAM_ERROR);
+
+ g_return_val_if_fail (PRIVATE (a_this)->next_byte_index <=
+ PRIVATE (a_this)->nb_bytes, CR_BAD_PARAM_ERROR);
+
+ if (PRIVATE (a_this)->end_of_input == TRUE)
+ return CR_END_OF_INPUT_ERROR;
+
+ *a_byte = PRIVATE (a_this)->in_buf[PRIVATE (a_this)->next_byte_index];
+
+ if (PRIVATE (a_this)->nb_bytes -
+ PRIVATE (a_this)->next_byte_index < 2) {
+ PRIVATE (a_this)->end_of_input = TRUE;
+ } else {
+ PRIVATE (a_this)->next_byte_index++;
+ }
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_read_char:
+ *@a_this: the current instance of CRInput.
+ *@a_char: out parameter. The read character.
+ *
+ *Reads an unicode character from the current instance of
+ *#CRInput.
+ *
+ *Returns CR_OK upon successful completion, an error code
+ *otherwise.
+ */
+enum CRStatus
+cr_input_read_char (CRInput * a_this, guint32 * a_char)
+{
+ enum CRStatus status = CR_OK;
+ gulong consumed = 0,
+ nb_bytes_left = 0;
+
+ g_return_val_if_fail (a_this && PRIVATE (a_this) && a_char,
+ CR_BAD_PARAM_ERROR);
+
+ if (PRIVATE (a_this)->end_of_input == TRUE)
+ return CR_END_OF_INPUT_ERROR;
+
+ nb_bytes_left = cr_input_get_nb_bytes_left (a_this);
+
+ if (nb_bytes_left < 1) {
+ return CR_END_OF_INPUT_ERROR;
+ }
+
+ status = cr_utils_read_char_from_utf8_buf
+ (PRIVATE (a_this)->in_buf
+ +
+ PRIVATE (a_this)->next_byte_index,
+ nb_bytes_left, a_char, &consumed);
+
+ if (status == CR_OK) {
+ /*update next byte index */
+ PRIVATE (a_this)->next_byte_index += consumed;
+
+ /*update line and column number */
+ if (PRIVATE (a_this)->end_of_line == TRUE) {
+ PRIVATE (a_this)->col = 1;
+ PRIVATE (a_this)->line++;
+ PRIVATE (a_this)->end_of_line = FALSE;
+ } else if (*a_char != '\n') {
+ PRIVATE (a_this)->col++;
+ }
+
+ if (*a_char == '\n') {
+ PRIVATE (a_this)->end_of_line = TRUE;
+ }
+ }
+
+ return status;
+}
+
+/**
+ * cr_input_set_line_num:
+ *@a_this: the "this pointer" of the current instance of #CRInput.
+ *@a_line_num: the new line number.
+ *
+ *Setter of the current line number.
+ *
+ *Return CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_set_line_num (CRInput * a_this, glong a_line_num)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), CR_BAD_PARAM_ERROR);
+
+ PRIVATE (a_this)->line = a_line_num;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_get_line_num:
+ *@a_this: the "this pointer" of the current instance of #CRInput.
+ *@a_line_num: the returned line number.
+ *
+ *Getter of the current line number.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_get_line_num (CRInput const * a_this, glong * a_line_num)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this)
+ && a_line_num, CR_BAD_PARAM_ERROR);
+
+ *a_line_num = PRIVATE (a_this)->line;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_set_column_num:
+ *@a_this: the "this pointer" of the current instance of #CRInput.
+ *@a_col: the new column number.
+ *
+ *Setter of the current column number.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_set_column_num (CRInput * a_this, glong a_col)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), CR_BAD_PARAM_ERROR);
+
+ PRIVATE (a_this)->col = a_col;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_get_column_num:
+ *@a_this: the "this pointer" of the current instance of #CRInput.
+ *@a_col: out parameter
+ *
+ *Getter of the current column number.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_get_column_num (CRInput const * a_this, glong * a_col)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this) && a_col,
+ CR_BAD_PARAM_ERROR);
+
+ *a_col = PRIVATE (a_this)->col;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_increment_line_num:
+ *@a_this: the "this pointer" of the current instance of #CRInput.
+ *@a_increment: the increment to add to the line number.
+ *
+ *Increments the current line number.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_increment_line_num (CRInput * a_this, glong a_increment)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), CR_BAD_PARAM_ERROR);
+
+ PRIVATE (a_this)->line += a_increment;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_increment_col_num:
+ *@a_this: the "this pointer" of the current instance of #CRInput.
+ *@a_increment: the increment to add to the column number.
+ *
+ *Increments the current column number.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_increment_col_num (CRInput * a_this, glong a_increment)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), CR_BAD_PARAM_ERROR);
+
+ PRIVATE (a_this)->col += a_increment;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_consume_char:
+ *@a_this: the this pointer.
+ *@a_char: the character to consume. If set to zero,
+ *consumes any character.
+ *
+ *Consumes the next character of the input stream if
+ *and only if that character equals a_char.
+ *
+ *Returns CR_OK upon successful completion, CR_PARSING_ERROR if
+ *next char is different from a_char, an other error code otherwise
+ */
+enum CRStatus
+cr_input_consume_char (CRInput * a_this, guint32 a_char)
+{
+ guint32 c;
+ enum CRStatus status;
+
+ g_return_val_if_fail (a_this && PRIVATE (a_this), CR_BAD_PARAM_ERROR);
+
+ if ((status = cr_input_peek_char (a_this, &c)) != CR_OK) {
+ return status;
+ }
+
+ if (c == a_char || a_char == 0) {
+ status = cr_input_read_char (a_this, &c);
+ } else {
+ return CR_PARSING_ERROR;
+ }
+
+ return status;
+}
+
+/**
+ * cr_input_consume_chars:
+ *@a_this: the this pointer of the current instance of #CRInput.
+ *@a_char: the character to consume.
+ *@a_nb_char: in/out parameter. The number of characters to consume.
+ *If set to a negative value, the function will consume all the occurrences
+ *of a_char found.
+ *After return, if the return value equals CR_OK, this variable contains
+ *the number of characters actually consumed.
+ *
+ *Consumes up to a_nb_char occurrences of the next contiguous characters
+ *which equal a_char. Note that the next character of the input stream
+ **MUST* equal a_char to trigger the consumption, or else, the error
+ *code CR_PARSING_ERROR is returned.
+ *If the number of contiguous characters that equals a_char is less than
+ *a_nb_char, then this function consumes all the characters it can consume.
+ *
+ *Returns CR_OK if at least one character has been consumed, an error code
+ *otherwise.
+ */
+enum CRStatus
+cr_input_consume_chars (CRInput * a_this, guint32 a_char, gulong * a_nb_char)
+{
+ enum CRStatus status = CR_OK;
+ gulong nb_consumed = 0;
+
+ g_return_val_if_fail (a_this && PRIVATE (a_this) && a_nb_char,
+ CR_BAD_PARAM_ERROR);
+
+ g_return_val_if_fail (a_char != 0 || a_nb_char != NULL,
+ CR_BAD_PARAM_ERROR);
+
+ for (nb_consumed = 0; ((status == CR_OK)
+ && (*a_nb_char > 0
+ && nb_consumed < *a_nb_char));
+ nb_consumed++) {
+ status = cr_input_consume_char (a_this, a_char);
+ }
+
+ *a_nb_char = nb_consumed;
+
+ if ((nb_consumed > 0)
+ && ((status == CR_PARSING_ERROR)
+ || (status == CR_END_OF_INPUT_ERROR))) {
+ status = CR_OK;
+ }
+
+ return status;
+}
+
+/**
+ * cr_input_consume_white_spaces:
+ *@a_this: the "this pointer" of the current instance of #CRInput.
+ *@a_nb_chars: in/out parameter. The number of white spaces to
+ *consume. After return, holds the number of white spaces actually consumed.
+ *
+ *Same as cr_input_consume_chars() but this one consumes white
+ *spaces.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_consume_white_spaces (CRInput * a_this, gulong * a_nb_chars)
+{
+ enum CRStatus status = CR_OK;
+ guint32 cur_char = 0,
+ nb_consumed = 0;
+
+ g_return_val_if_fail (a_this && PRIVATE (a_this) && a_nb_chars,
+ CR_BAD_PARAM_ERROR);
+
+ for (nb_consumed = 0;
+ ((*a_nb_chars > 0) && (nb_consumed < *a_nb_chars));
+ nb_consumed++) {
+ status = cr_input_peek_char (a_this, &cur_char);
+ if (status != CR_OK)
+ break;
+
+ /*if the next char is a white space, consume it ! */
+ if (cr_utils_is_white_space (cur_char) == TRUE) {
+ status = cr_input_read_char (a_this, &cur_char);
+ if (status != CR_OK)
+ break;
+ continue;
+ }
+
+ break;
+
+ }
+
+ *a_nb_chars = (gulong) nb_consumed;
+
+ if (nb_consumed && status == CR_END_OF_INPUT_ERROR) {
+ status = CR_OK;
+ }
+
+ return status;
+}
+
+/**
+ * cr_input_peek_char:
+ *@a_this: the current instance of #CRInput.
+ *@a_char: out parameter. The returned character.
+ *
+ *Same as cr_input_read_char() but does not update the
+ *internal state of the input stream. The next call
+ *to cr_input_peek_char() or cr_input_read_char() will thus
+ *return the same character as the current one.
+ *
+ *Returns CR_OK upon successful completion, an error code
+ *otherwise.
+ */
+enum CRStatus
+cr_input_peek_char (CRInput const * a_this, guint32 * a_char)
+{
+ enum CRStatus status = CR_OK;
+ gulong consumed = 0,
+ nb_bytes_left = 0;
+
+ g_return_val_if_fail (a_this && PRIVATE (a_this)
+ && a_char, CR_BAD_PARAM_ERROR);
+
+ if (PRIVATE (a_this)->next_byte_index >=
+ PRIVATE (a_this)->in_buf_size) {
+ return CR_END_OF_INPUT_ERROR;
+ }
+
+ nb_bytes_left = cr_input_get_nb_bytes_left (a_this);
+
+ if (nb_bytes_left < 1) {
+ return CR_END_OF_INPUT_ERROR;
+ }
+
+ status = cr_utils_read_char_from_utf8_buf
+ (PRIVATE (a_this)->in_buf +
+ PRIVATE (a_this)->next_byte_index,
+ nb_bytes_left, a_char, &consumed);
+
+ return status;
+}
+
+/**
+ * cr_input_peek_byte:
+ *@a_this: the current instance of #CRInput.
+ *@a_origin: the origin to consider in the calculation
+ *of the position of the byte to peek.
+ *@a_offset: the offset of the byte to peek, starting from
+ *the origin specified by a_origin.
+ *@a_byte: out parameter the peeked byte.
+ *
+ *Gets a byte from the input stream,
+ *starting from the current position in the input stream.
+ *Unlike cr_input_peek_next_byte() this method
+ *does not update the state of the current input stream.
+ *Subsequent calls to cr_input_peek_byte with the same arguments
+ *will return the same byte.
+ *
+ *Returns CR_OK upon successful completion or,
+ *CR_BAD_PARAM_ERROR if at least one of the parameters is invalid;
+ *CR_OUT_OF_BOUNDS_ERROR if the indexed byte is out of bounds.
+ */
+enum CRStatus
+cr_input_peek_byte (CRInput const * a_this, enum CRSeekPos a_origin,
+ gulong a_offset, guchar * a_byte)
+{
+ gulong abs_offset = 0;
+
+ g_return_val_if_fail (a_this && PRIVATE (a_this)
+ && a_byte, CR_BAD_PARAM_ERROR);
+
+ switch (a_origin) {
+
+ case CR_SEEK_CUR:
+ abs_offset = PRIVATE (a_this)->next_byte_index - 1 + a_offset;
+ break;
+
+ case CR_SEEK_BEGIN:
+ abs_offset = a_offset;
+ break;
+
+ case CR_SEEK_END:
+ abs_offset = PRIVATE (a_this)->in_buf_size - 1 - a_offset;
+ break;
+
+ default:
+ return CR_BAD_PARAM_ERROR;
+ }
+
+ if (abs_offset < PRIVATE (a_this)->in_buf_size) {
+
+ *a_byte = PRIVATE (a_this)->in_buf[abs_offset];
+
+ return CR_OK;
+
+ } else {
+ return CR_END_OF_INPUT_ERROR;
+ }
+}
+
+/**
+ * cr_input_peek_byte2:
+ *@a_this: the current byte input stream.
+ *@a_offset: the offset of the byte to peek, starting
+ *from the current input position pointer.
+ *@a_eof: out parameter. Is set to true is we reach end of
+ *stream. If set to NULL by the caller, this parameter is not taken
+ *in account.
+ *
+ *Same as cr_input_peek_byte() but with a simplified
+ *interface.
+ *
+ *Returns the read byte or 0 if something bad happened.
+ */
+guchar
+cr_input_peek_byte2 (CRInput const * a_this, gulong a_offset, gboolean * a_eof)
+{
+ guchar result = 0;
+ enum CRStatus status = CR_ERROR;
+
+ g_return_val_if_fail (a_this && PRIVATE (a_this), 0);
+
+ if (a_eof)
+ *a_eof = FALSE;
+
+ status = cr_input_peek_byte (a_this, CR_SEEK_CUR, a_offset, &result);
+
+ if ((status == CR_END_OF_INPUT_ERROR)
+ && a_eof)
+ *a_eof = TRUE;
+
+ return result;
+}
+
+/**
+ * cr_input_get_byte_addr:
+ *@a_this: the current instance of #CRInput.
+ *@a_offset: the offset of the byte in the input stream starting
+ *from the beginning of the stream.
+ *
+ *Gets the memory address of the byte located at a given offset
+ *in the input stream.
+ *
+ *Returns the address, otherwise NULL if an error occurred.
+ */
+guchar *
+cr_input_get_byte_addr (CRInput * a_this, gulong a_offset)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), NULL);
+
+ if (a_offset >= PRIVATE (a_this)->nb_bytes) {
+ return NULL;
+ }
+
+ return &PRIVATE (a_this)->in_buf[a_offset];
+}
+
+/**
+ * cr_input_get_cur_byte_addr:
+ *@a_this: the current input stream
+ *@a_offset: out parameter. The returned address.
+ *
+ *Gets the address of the current character pointer.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_get_cur_byte_addr (CRInput * a_this, guchar ** a_offset)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this) && a_offset,
+ CR_BAD_PARAM_ERROR);
+
+ if (!PRIVATE (a_this)->next_byte_index) {
+ return CR_START_OF_INPUT_ERROR;
+ }
+
+ *a_offset = cr_input_get_byte_addr
+ (a_this, PRIVATE (a_this)->next_byte_index - 1);
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_seek_index:
+ *@a_this: the current instance of #CRInput.
+ *@a_origin: the origin to consider during the calculation
+ *of the absolute position of the new "current byte index".
+ *@a_pos: the relative offset of the new "current byte index."
+ *This offset is relative to the origin a_origin.
+ *
+ *Sets the "current byte index" of the current instance
+ *of #CRInput. Next call to cr_input_get_byte() will return
+ *the byte next after the new "current byte index".
+ *
+ *Returns CR_OK upon successful completion otherwise returns
+ *CR_BAD_PARAM_ERROR if at least one of the parameters is not valid
+ *or CR_OUT_BOUNDS_ERROR in case of error.
+ */
+enum CRStatus
+cr_input_seek_index (CRInput * a_this, enum CRSeekPos a_origin, gint a_pos)
+{
+
+ glong abs_offset = 0;
+
+ g_return_val_if_fail (a_this && PRIVATE (a_this), CR_BAD_PARAM_ERROR);
+
+ switch (a_origin) {
+
+ case CR_SEEK_CUR:
+ abs_offset = PRIVATE (a_this)->next_byte_index - 1 + a_pos;
+ break;
+
+ case CR_SEEK_BEGIN:
+ abs_offset = a_pos;
+ break;
+
+ case CR_SEEK_END:
+ abs_offset = PRIVATE (a_this)->in_buf_size - 1 - a_pos;
+ break;
+
+ default:
+ return CR_BAD_PARAM_ERROR;
+ }
+
+ if ((abs_offset > 0)
+ && (gulong) abs_offset < PRIVATE (a_this)->nb_bytes) {
+
+ /*update the input stream's internal state */
+ PRIVATE (a_this)->next_byte_index = abs_offset + 1;
+
+ return CR_OK;
+ }
+
+ return CR_OUT_OF_BOUNDS_ERROR;
+}
+
+/**
+ * cr_input_get_cur_pos:
+ *@a_this: the current instance of #CRInput.
+ *@a_pos: out parameter. The returned position.
+ *
+ *Gets the position of the "current byte index" which
+ *is basically the position of the last returned byte in the
+ *input stream.
+ *
+ *Returns CR_OK upon successful completion. Otherwise,
+ *CR_BAD_PARAMETER_ERROR if at least one of the arguments is invalid.
+ *CR_START_OF_INPUT if no call to either cr_input_read_byte()
+ *or cr_input_seek_index() have been issued before calling
+ *cr_input_get_cur_pos()
+ *Note that the out parameters of this function are valid if and only if this
+ *function returns CR_OK.
+ */
+enum CRStatus
+cr_input_get_cur_pos (CRInput const * a_this, CRInputPos * a_pos)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this) && a_pos,
+ CR_BAD_PARAM_ERROR);
+
+ a_pos->next_byte_index = PRIVATE (a_this)->next_byte_index;
+ a_pos->line = PRIVATE (a_this)->line;
+ a_pos->col = PRIVATE (a_this)->col;
+ a_pos->end_of_line = PRIVATE (a_this)->end_of_line;
+ a_pos->end_of_file = PRIVATE (a_this)->end_of_input;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_get_parsing_location:
+ *@a_this: the current instance of #CRInput
+ *@a_loc: the set parsing location.
+ *
+ *Gets the current parsing location.
+ *The Parsing location is a public datastructure that
+ *represents the current line/column/byte offset/ in the input
+ *stream.
+ *
+ *Returns CR_OK upon successful completion, an error
+ *code otherwise.
+ */
+enum CRStatus
+cr_input_get_parsing_location (CRInput const *a_this,
+ CRParsingLocation *a_loc)
+{
+ g_return_val_if_fail (a_this
+ && PRIVATE (a_this)
+ && a_loc,
+ CR_BAD_PARAM_ERROR) ;
+
+ a_loc->line = PRIVATE (a_this)->line ;
+ a_loc->column = PRIVATE (a_this)->col ;
+ if (PRIVATE (a_this)->next_byte_index) {
+ a_loc->byte_offset = PRIVATE (a_this)->next_byte_index - 1 ;
+ } else {
+ a_loc->byte_offset = PRIVATE (a_this)->next_byte_index ;
+ }
+ return CR_OK ;
+}
+
+/**
+ * cr_input_get_cur_index:
+ *@a_this: the "this pointer" of the current instance of
+ *#CRInput
+ *@a_index: out parameter. The returned index.
+ *
+ *Getter of the next byte index.
+ *It actually returns the index of the
+ *next byte to be read.
+ *
+ *Returns CR_OK upon successful completion, an error code
+ *otherwise.
+ */
+enum CRStatus
+cr_input_get_cur_index (CRInput const * a_this, glong * a_index)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this)
+ && a_index, CR_BAD_PARAM_ERROR);
+
+ *a_index = PRIVATE (a_this)->next_byte_index;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_set_cur_index:
+ *@a_this: the "this pointer" of the current instance
+ *of #CRInput .
+ *@a_index: the new index to set.
+ *
+ *Setter of the next byte index.
+ *It sets the index of the next byte to be read.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_set_cur_index (CRInput * a_this, glong a_index)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), CR_BAD_PARAM_ERROR);
+
+ PRIVATE (a_this)->next_byte_index = a_index;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_set_end_of_file:
+ *@a_this: the current instance of #CRInput.
+ *@a_eof: the new end of file flag.
+ *
+ *Sets the end of file flag.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_set_end_of_file (CRInput * a_this, gboolean a_eof)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), CR_BAD_PARAM_ERROR);
+
+ PRIVATE (a_this)->end_of_input = a_eof;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_get_end_of_file:
+ *@a_this: the current instance of #CRInput.
+ *@a_eof: out parameter the place to put the end of
+ *file flag.
+ *
+ *Gets the end of file flag.
+ *
+ *Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_get_end_of_file (CRInput const * a_this, gboolean * a_eof)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this)
+ && a_eof, CR_BAD_PARAM_ERROR);
+
+ *a_eof = PRIVATE (a_this)->end_of_input;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_set_end_of_line:
+ *@a_this: the current instance of #CRInput.
+ *@a_eol: the new end of line flag.
+ *
+ *Sets the end of line flag.
+ *
+ *Returns CR_OK upon successful completion, an error code
+ *otherwise.
+ */
+enum CRStatus
+cr_input_set_end_of_line (CRInput * a_this, gboolean a_eol)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this), CR_BAD_PARAM_ERROR);
+
+ PRIVATE (a_this)->end_of_line = a_eol;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_get_end_of_line:
+ *@a_this: the current instance of #CRInput
+ *@a_eol: out parameter. The place to put
+ *the returned flag
+ *
+ *Gets the end of line flag of the current input.
+ *
+ *Returns CR_OK upon successful completion, an error code
+ *otherwise.
+ */
+enum CRStatus
+cr_input_get_end_of_line (CRInput const * a_this, gboolean * a_eol)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this)
+ && a_eol, CR_BAD_PARAM_ERROR);
+
+ *a_eol = PRIVATE (a_this)->end_of_line;
+
+ return CR_OK;
+}
+
+/**
+ * cr_input_set_cur_pos:
+ *@a_this: the "this pointer" of the current instance of
+ *#CRInput.
+ *@a_pos: the new position.
+ *
+ *Sets the current position in the input stream.
+ *
+ * Returns CR_OK upon successful completion, an error code otherwise.
+ */
+enum CRStatus
+cr_input_set_cur_pos (CRInput * a_this, CRInputPos const * a_pos)
+{
+ g_return_val_if_fail (a_this && PRIVATE (a_this) && a_pos,
+ CR_BAD_PARAM_ERROR);
+
+ cr_input_set_column_num (a_this, a_pos->col);
+ cr_input_set_line_num (a_this, a_pos->line);
+ cr_input_set_cur_index (a_this, a_pos->next_byte_index);
+ cr_input_set_end_of_line (a_this, a_pos->end_of_line);
+ cr_input_set_end_of_file (a_this, a_pos->end_of_file);
+
+ return CR_OK;
+}