parser lib for my games
| 1 | #include <parser.h> |
| 2 | |
| 3 | uint8_t main_buffer[BUF_LEN]; |
| 4 | |
| 5 | uint16_t start = 0; |
| 6 | uint16_t end = 0; |
| 7 | |
| 8 | uint16_t length = 0; |
| 9 | |
| 10 | |
| 11 | int add_to_buf(uint8_t *input, uint16_t input_length) { |
| 12 | |
| 13 | if (BUF_LEN - length < input_length) |
| 14 | return 0; |
| 15 | |
| 16 | uint16_t space_end = BUF_LEN - end; |
| 17 | |
| 18 | if (input_length <= space_end) { |
| 19 | memcpy(main_buffer + end, input, input_length); |
| 20 | } else { |
| 21 | memcpy(main_buffer + end, input, space_end); |
| 22 | memcpy(main_buffer, input + space_end, input_length - space_end); |
| 23 | } |
| 24 | |
| 25 | end = (end + input_length) % BUF_LEN; |
| 26 | length += input_length; |
| 27 | |
| 28 | return 1; |
| 29 | } |
| 30 | |
| 31 | |
| 32 | uint16_t next_pos(uint16_t starting_position) { |
| 33 | return (starting_position + 1) % BUF_LEN; |
| 34 | } |
| 35 | |
| 36 | |
| 37 | keypress parse_input() { |
| 38 | |
| 39 | if(length == 0) |
| 40 | return NO_KEY; |
| 41 | |
| 42 | keypress output = UNKNOWN; |
| 43 | |
| 44 | uint8_t next_char = tolower(main_buffer[start]); |
| 45 | uint16_t next_position = next_pos(start); |
| 46 | |
| 47 | |
| 48 | if (next_char == '\033') { |
| 49 | |
| 50 | if (length < ARROW_LEN) { |
| 51 | output = INCOMPLETE; |
| 52 | next_position = start; |
| 53 | } else { |
| 54 | |
| 55 | length--; |
| 56 | |
| 57 | if (main_buffer[next_position] == '[') { |
| 58 | next_position = next_pos(next_position); |
| 59 | |
| 60 | length--; |
| 61 | |
| 62 | uint8_t escape_code = main_buffer[next_position]; |
| 63 | |
| 64 | switch(escape_code) { |
| 65 | case 'A': |
| 66 | output = UP_ARROW; |
| 67 | break; |
| 68 | case 'B': |
| 69 | output = DOWN_ARROW; |
| 70 | break; |
| 71 | case 'C': |
| 72 | output = RIGHT_ARROW; |
| 73 | break; |
| 74 | case 'D': |
| 75 | output = LEFT_ARROW; |
| 76 | break; |
| 77 | default: |
| 78 | break; |
| 79 | } |
| 80 | |
| 81 | length--; |
| 82 | |
| 83 | next_position = next_pos(next_position); |
| 84 | } |
| 85 | } |
| 86 | |
| 87 | } else { |
| 88 | |
| 89 | length--; |
| 90 | |
| 91 | if (next_char == 'p') { |
| 92 | output = P_KEY; |
| 93 | } else if(next_char == 'q') { |
| 94 | output = Q_KEY; |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | start = next_position; |
| 99 | |
| 100 | return output; |
| 101 | } |
| 102 | |
| 103 | void break_unfinished() { |
| 104 | while (length--) |
| 105 | start = next_pos(start); |
| 106 | } |