/* * Symbol Barcode Scanner Reader Software * Written by Andy Stewart * June 5, 2007 * * 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 * * Set the debug variable to 1 to get some debug printouts. * * One must have the Linux kernel sources installed in order for this to compile. * * To build it: * gcc -o bar bar.c * * Note: this code was tested on Linux kernel rev. 2.6.32 (FOX Board G20) * */ #include #include #include #include #include "string.h" #include /* defined at the end of this file */ char cvt_ev_char(int); void debug_rcvd_event(struct input_event *); #define MAX_IN_SIZE 30 main(int argc, char *argv[]) { int debug = 0; /* set this to 1 to get debug info */ struct input_event ev[64]; /* each scan causes more than one event...get them all */ int fd = -1; /* file descriptor for the scanner device */ int bytes_read = 0; /* number of bytes read by the read function */ int i; /* loop variable */ char scanner_in[30]; /* set this bigger if scanned input is more than 30 characters */ char scan_char; /* this holds one char at a time...will be concatenated into scanner_in[] */ int wr_ptr = 0; /* points into scanner_in so we know where to put the next scan_char */ printf("Go ahead and scan something - press ctrl_C when finished.\n"); printf("Look for printouts which say: Input from Scanner\n"); printf("Ignore other printouts\n"); /* The device interface can be found in /dev/input/by-id/*Symbol*, which should be a link * to /dev/input/eventN, where N is some number. One may need to adjust the permissions of the * eventN file. * * Yeah, I know it sucks for me to have hardcoded this value...sorry, I was too lazy to compute it. */ if ((fd = open("/dev/input/event1", O_RDONLY)) < 0) { printf("Error opening file descriptor - do you have sufficient permission? Maybe it is incorrectly hardcoded - check the source. Exiting.\n"); return -1; } while (1) { bytes_read = read(fd, &ev, sizeof(struct input_event) * 64); if (bytes_read < 0) { printf("ERROR: can't properly read from device\n"); return -1; } for (i=0; i < (int) (bytes_read / sizeof(struct input_event)); i++) { /* Look for a "key press" event */ if ((ev[i].type == EV_KEY) && (ev[i].value == 1)) { if (ev[i].code != KEY_LEFTSHIFT) { scan_char = cvt_ev_char(ev[i].code); /* Extract the character from the event */ if (debug) { debug_rcvd_event(&ev[i]); printf("Scan char: %c\n", scan_char); } if (ev[i].code != KEY_ENTER) { scanner_in[wr_ptr++] = scan_char; } else { scanner_in[wr_ptr] = '\0'; printf("Input from Scanner: \"%s\"\n", scanner_in); wr_ptr = 0; } } /* if (ev[i].code ...) */ } /* if ((ev[i].type.....)) */ } /* for (i=0...) */ } /* while (1) */ close(fd); } /* main */ /* * cvt_ev_char: convert the code in the "keyboard" event to an ASCII character * The character definitions came from /usr/include/linux/input.h * Assumption is that barcodes can only have 0-9, A-Z so other * codes have been removed from the list below. * */ char cvt_ev_char(int foo) { char bar; switch (foo) { case KEY_0: bar = '0'; break; case KEY_1: bar = '1'; break; case KEY_2: bar = '2'; break; case KEY_3: bar = '3'; break; case KEY_4: bar = '4'; break; case KEY_5: bar = '5'; break; case KEY_6: bar = '6'; break; case KEY_7: bar = '7'; break; case KEY_8: bar = '8'; break; case KEY_9: bar = '9'; break; case KEY_A: bar = 'A'; break; case KEY_B: bar = 'B'; break; case KEY_C: bar = 'C'; break; case KEY_D: bar = 'D'; break; case KEY_E: bar = 'E'; break; case KEY_F: bar = 'F'; break; case KEY_G: bar = 'G'; break; case KEY_H: bar = 'H'; break; case KEY_I: bar = 'I'; break; case KEY_J: bar = 'J'; break; case KEY_K: bar = 'K'; break; case KEY_L: bar = 'L'; break; case KEY_M: bar = 'M'; break; case KEY_N: bar = 'N'; break; case KEY_O: bar = 'O'; break; case KEY_P: bar = 'P'; break; case KEY_Q: bar = 'Q'; break; case KEY_R: bar = 'R'; break; case KEY_S: bar = 'S'; break; case KEY_T: bar = 'T'; break; case KEY_U: bar = 'U'; break; case KEY_V: bar = 'V'; break; case KEY_W: bar = 'W'; break; case KEY_X: bar = 'X'; break; case KEY_Y: bar = 'Y'; break; case KEY_Z: bar = 'Z'; break; case KEY_ENTER: bar = '\n'; break; default: bar = '?'; } return bar; } void debug_rcvd_event(struct input_event *ev) { char type_str[15]; switch (ev->type) { case EV_SYN: strcpy(type_str, "EV_SYN"); break; case EV_KEY: strcpy(type_str, "EV_KEY"); break; case EV_REL: strcpy(type_str, "EV_REL"); break; case EV_ABS: strcpy(type_str, "EV_ABS"); break; case EV_MSC: strcpy(type_str, "EV_MSC"); break; case EV_SW: strcpy(type_str, "EV_SW"); break; case EV_LED: strcpy(type_str, "EV_LED"); break; case EV_SND: strcpy(type_str, "EV_SND"); break; case EV_REP: strcpy(type_str, "EV_REP"); break; case EV_FF: strcpy(type_str, "EV_FF"); break; case EV_PWR: strcpy(type_str, "EV_PWR"); break; case EV_MAX: strcpy(type_str, "EV_MAX"); break; case EV_FF_STATUS: strcpy(type_str, "EV_FF_STATUS"); break; default: strcpy(type_str, "UNK"); } printf("Event: time %ld.%06ld, type %s, code %d, value %d\n", ev->time.tv_sec, ev->time.tv_usec, type_str, ev->code, ev->value); }