+/* picoproj - communication with AM7xxx based USB pico projectors
+ *
+ * Copyright (C) 2011 Antonio Ospite <ospite@studenti.unina.it>
+ *
+ * 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/>.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <endian.h>
+#include <errno.h>
+
+/*
+ * Examples of a packet headers:
+ *
+ * Image widget:
+ * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ * +02|00|00|00|00|10|3e|10|01|00|00|00|20|03|00|00|e0|01|00|00|53|E8|00|00+
+ * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ *
+ * Brightness widget:
+ * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ * +04|00|00|00|00|0c|ff|ff|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00|00+
+ * +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ */
+
+#define AM7x01_PACKET_TYPE_INIT 0x01
+#define AM7x01_PACKET_TYPE_IMAGE 0x02
+#define AM7x01_PACKET_TYPE_POWER 0x04
+#define AM7x01_PACKET_TYPE_UNKNOWN 0x05
+
+struct buffer {
+ unsigned int len;
+ uint8_t *data;
+};
+
+struct header{
+ uint32_t packet_type;
+ uint32_t unknown1;
+ uint32_t unknown2;
+ uint32_t width;
+ uint32_t height;
+ uint32_t payload_size;
+};
+
+struct packet {
+ struct header header;
+ uint8_t payload[];
+};
+
+static struct buffer *packet_allocate_buffer(struct packet *p)
+{
+ struct buffer *buffer;
+
+ if (p == NULL) {
+ perror("packet NULL");
+ return NULL;
+ }
+
+ buffer = malloc(sizeof(*buffer));
+ if (buffer == NULL) {
+ perror("malloc buffer");
+ return NULL;
+ }
+
+ buffer->len = sizeof(p->header); /* + p->header.payload_size; */
+
+ buffer->data = malloc(buffer->len);
+ if (buffer->data == NULL) {
+ perror("malloc buffer->data");
+ free(buffer);
+ return NULL;
+ }
+ return buffer;
+}
+
+static void packet_free_buffer(struct buffer *buffer)
+{
+ free(buffer->data);
+ free(buffer);
+ buffer = NULL;
+}
+
+static int packet_pack(struct packet *p, struct buffer *buffer)
+{
+ unsigned int offset;
+ uint32_t tmp;
+
+ if (p == NULL || buffer == NULL)
+ return -EINVAL;
+
+ /* TODO: check for packet payload being NULL? */
+ if (buffer->data == NULL || buffer->len < sizeof(*p))
+ return -EINVAL;
+
+ offset = 0;
+
+ tmp = htole32(p->header.packet_type);
+ memcpy(buffer->data + offset, &tmp, sizeof(p->header.packet_type));
+ offset += sizeof(p->header.packet_type);
+
+ tmp = htole32(p->header.unknown1);
+ memcpy(buffer->data + offset, &tmp, sizeof(p->header.unknown1));
+ offset += sizeof(p->header.unknown1);
+
+ tmp = htole32(p->header.unknown2);
+ memcpy(buffer->data + offset, &tmp, sizeof(p->header.unknown2));
+ offset += sizeof(p->header.unknown2);
+
+ tmp = htole32(p->header.width);
+ memcpy(buffer->data + offset, &tmp, sizeof(p->header.width));
+ offset += sizeof(p->header.width);
+
+ tmp = htole32(p->header.height);
+ memcpy(buffer->data + offset, &tmp, sizeof(p->header.height));
+ offset += sizeof(p->header.height);
+
+ tmp = htole32(p->header.payload_size);
+ memcpy(buffer->data + offset, &tmp, sizeof(p->header.payload_size));
+ offset += sizeof(p->header.payload_size);
+
+ /* TODO memcpy payload of size */
+
+ return 0;
+}
+
+static int packet_unpack(struct buffer *buffer, struct packet *p)
+{
+ unsigned int offset;
+ uint32_t tmp;
+
+ if (p == NULL || buffer == NULL)
+ return -EINVAL;
+
+ /* TODO: check for packet payload being NULL? */
+ if (buffer->data == NULL || buffer->len < sizeof(*p))
+ return -EINVAL;
+
+ offset = 0;
+
+ memcpy(&tmp, buffer->data + offset, sizeof(p->header.packet_type));
+ p->header.packet_type = le32toh(tmp);
+ offset += sizeof(p->header.packet_type);
+
+ memcpy(&tmp, buffer->data + offset, sizeof(p->header.unknown1));
+ p->header.unknown1 = le32toh(tmp);
+ offset += sizeof(p->header.unknown1);
+
+ memcpy(&tmp, buffer->data + offset, sizeof(p->header.unknown2));
+ p->header.unknown2 = le32toh(tmp);
+ offset += sizeof(p->header.unknown2);
+
+ memcpy(&tmp, buffer->data + offset, sizeof(p->header.width));
+ p->header.width = le32toh(tmp);
+ offset += sizeof(p->header.width);
+
+ memcpy(&tmp, buffer->data + offset, sizeof(p->header.height));
+ p->header.height = le32toh(tmp);
+ offset += sizeof(p->header.height);
+
+ memcpy(&tmp, buffer->data + offset, sizeof(p->header.payload_size));
+ p->header.payload_size = le32toh(tmp);
+ offset += sizeof(p->header.payload_size);
+
+ /* malloc & memcpy payload of size p->header.payload_size */
+
+ return 0;
+}
+
+static void packet_dump_header(struct packet *p)
+{
+ if (p == NULL)
+ return;
+
+ printf("packet_type: 0x%08x (%u)\n", p->header.packet_type, p->header.packet_type);
+ printf("unknown1: 0x%08x (%u)\n", p->header.unknown1, p->header.unknown1);
+ printf("unknown2: 0x%08x (%u)\n", p->header.unknown2, p->header.unknown2);
+ printf("width: 0x%08x (%u)\n", p->header.width, p->header.width);
+ printf("height: 0x%08x (%u)\n", p->header.height, p->header.height);
+ printf("size: 0x%08x (%u)\n", p->header.payload_size, p->header.payload_size);
+ fflush(stdout);
+}
+
+static void packet_dump_buffer(struct buffer *buffer)
+{
+ unsigned int i;
+
+ if (buffer == NULL)
+ return;
+
+ if (buffer->data == NULL)
+ return;
+
+ for (i = 0; i < buffer->len; i++) {
+ printf("%02hhX%c", buffer->data[i], (i < buffer->len - 1) ? ' ' : '\n');
+ }
+ fflush(stdout);
+}
+
+int main(void)
+{
+ struct packet p1 = {
+ .header = {
+ .packet_type = AM7x01_PACKET_TYPE_IMAGE,
+ .unknown1 = le32toh(0x103e1000),
+ .unknown2 = le32toh(0x00000001),
+ .width = 800,
+ .height = 480,
+ .payload_size = 59475,
+ },
+ /* TODO initialize payload */
+ };
+ struct buffer *buffer = NULL;
+ struct packet p2;
+ int ret;
+
+ packet_dump_header(&p1);
+
+ buffer = packet_allocate_buffer(&p1);
+ if (buffer == NULL) {
+ fprintf(stderr, "Cannot allocate the buffer.\n");
+ exit(EXIT_FAILURE);
+ }
+
+ ret = packet_pack(&p1, buffer);
+ if (ret < 0) {
+ fprintf(stderr, "Cannot pack the packet.\n");
+ exit(EXIT_FAILURE);
+ }
+
+ packet_dump_buffer(buffer);
+
+ ret = packet_unpack(buffer, &p2);
+ if (ret < 0) {
+ fprintf(stderr, "Cannot unpack the packet.\n");
+ exit(EXIT_FAILURE);
+ }
+
+ packet_dump_header(&p2);
+
+ packet_free_buffer(buffer);
+
+ exit(EXIT_SUCCESS);
+}
projects / libam7xxx.git / commitdiff