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Diffstat (limited to 'backend/ricoh2_buffer.c')
| -rw-r--r-- | backend/ricoh2_buffer.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/backend/ricoh2_buffer.c b/backend/ricoh2_buffer.c new file mode 100644 index 0000000..b8d7d90 --- /dev/null +++ b/backend/ricoh2_buffer.c @@ -0,0 +1,229 @@ +/* sane - Scanner Access Now Easy. + + Copyright (C) 2018 Stanislav Yuzvinsky + Based on the work done by viruxx + + This file is part of the SANE package. + + 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 2 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, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, + MA 02111-1307, USA. + + As a special exception, the authors of SANE give permission for + additional uses of the libraries contained in this release of SANE. + + The exception is that, if you link a SANE library with other files + to produce an executable, this does not by itself cause the + resulting executable to be covered by the GNU General Public + License. Your use of that executable is in no way restricted on + account of linking the SANE library code into it. + + This exception does not, however, invalidate any other reasons why + the executable file might be covered by the GNU General Public + License. + + If you submit changes to SANE to the maintainers to be included in + a subsequent release, you agree by submitting the changes that + those changes may be distributed with this exception intact. + + If you write modifications of your own for SANE, it is your choice + whether to permit this exception to apply to your modifications. + If you do not wish that, delete this exception notice. +*/ + +#include "../include/sane/config.h" + +#include <memory.h> +#include <assert.h> +#include <malloc.h> + +#include "../include/sane/sanei_debug.h" + +typedef struct ricoh2_buffer +{ + /* lifetime constants */ + SANE_Byte *data; + SANE_Int size; + SANE_Int pixels_per_line; + SANE_Int info_size; + SANE_Bool is_rgb; + + /* state */ + SANE_Int current_position; + SANE_Int remain_in_line; + +} +ricoh2_buffer; + +static ricoh2_buffer * +ricoh2_buffer_create (SANE_Int size, + SANE_Int pixels_per_line, + SANE_Int info_size, + SANE_Bool is_rgb) +{ + ricoh2_buffer *self; + assert (size > 0); + assert (pixels_per_line > 0); + assert (info_size >= 0); + + self = malloc (sizeof (ricoh2_buffer)); + if (!self) + return NULL; + + self->data = malloc (size); + if (!self->data) + { + free (self); + return NULL; + } + + self->size = size; + self->pixels_per_line = pixels_per_line; + self->info_size = info_size; + self->is_rgb = is_rgb; + + self->current_position = 0; + self->remain_in_line = pixels_per_line; + + + DBG (192, + "size = %d pixels_per_line = %d info_size = %d rgb? = %d pos = %d\n", + self->size, + self->pixels_per_line, + self->info_size, + self->is_rgb, + self->current_position); + + return self; +} + +/* destructor */ +static void +ricoh2_buffer_dispose (ricoh2_buffer *self) +{ + assert (self); + free (self->data); + free (self); +} + +static SANE_Byte * +ricoh2_buffer_get_internal_buffer (ricoh2_buffer *self) +{ + assert (self); + DBG (192, "engaging a buffer of size %d\n", self->size); + + self->current_position = 0; + self->remain_in_line = self->pixels_per_line; + + DBG (192, "remain in line = %d\n", self->remain_in_line); + + return self->data; +} + +static SANE_Int +ricoh2_buffer_get_bytes_remain (ricoh2_buffer *self) +{ + assert (self); + + DBG (192, + "bytes remain in the buffer %d\n", + self->size - self->current_position); + + return self->size - self->current_position; +} + +inline static SANE_Int +min (SANE_Int v1, SANE_Int v2) +{ + return v1 < v2 ? v1 : v2; +} + +static SANE_Int +ricoh2_buffer_get_data (ricoh2_buffer *self, + SANE_Byte *dest, + SANE_Int dest_size) +{ + SANE_Int actually_copied = 0; + SANE_Int pixels_to_copy; + SANE_Int bytes_per_pixel; + SANE_Int bytes_per_color; + SANE_Byte *src; + SANE_Byte *end; + + assert (self); + assert (dest); + assert (self->size > self->current_position); + + bytes_per_pixel = self->is_rgb ? 3 : 1; + bytes_per_color = self->pixels_per_line + self->info_size; + + DBG (192, + "trying to get %d bytes from the buffer, " + "while %d bytes in the line\n", + dest_size, + self->remain_in_line); + + for (pixels_to_copy = + min (dest_size / bytes_per_pixel, self->remain_in_line); + pixels_to_copy && self->size > self->current_position; + pixels_to_copy = + min (dest_size / bytes_per_pixel, self->remain_in_line)) + { + + DBG (192, + "providing %d bytes to the user (until the end of the line), " + "position in buffer is %d\n", + pixels_to_copy * bytes_per_pixel, + self->current_position); + + for (src = self->data + self->current_position, + end = src + pixels_to_copy; + src < end; + ++src) + { + *(dest++) = *(src); + if (bytes_per_pixel == 3) + { + *(dest++) = *(src + bytes_per_color); + *(dest++) = *(src + 2 * bytes_per_color); + } + } + + dest_size -= pixels_to_copy * bytes_per_pixel; + actually_copied += pixels_to_copy * bytes_per_pixel; + self->current_position += pixels_to_copy; + self->remain_in_line -= pixels_to_copy; + + // move to the next line + if (!self->remain_in_line) + { + self->current_position += self->info_size; + if (self->is_rgb) + self->current_position += 2 * bytes_per_color; + self->remain_in_line = self->pixels_per_line; + DBG (192, + "Line feed, new position is %d\n", + self->current_position); + } + + DBG (192, + "left in the buffer: %d\n", + self->size - self->current_position); + } + + /* invariant */ + assert (self->size >= self->current_position); + + return actually_copied; +} |