hid_detect.c File Reference

#include "stdlib.h"
#include "unistd.h"
#include "stdio.h"
#include "errno.h"
#include "stdint.h"
#include "string.h"

Include dependency graph for hid_detect.c:

Go to the source code of this file.

Macros
#define	LO(x)   ((x) & 0x0F)
#define	HI(x)   (((x) & 0xF0) >> 8)
#define	HEX(x)   ("0123456789abcdef"[(x)])

Functions
static const char *	type2str (uint8_t type)
int	main (int argc, char *argv[])

Macro Definition Documentation

#define HEX

(

x

)

("0123456789abcdef"[(x)])

Definition at line 41 of file hid_detect.c.

#define HI

(

x

)

(((x) & 0xF0) >> 8)

Definition at line 40 of file hid_detect.c.

#define LO

(

x

)

((x) & 0x0F)

Definition at line 39 of file hid_detect.c.

Function Documentation

int main	(	int	argc,
		char *	argv[]
	)

Definition at line 56 of file hid_detect.c.

References buf, and type2str().

{
        FILE *fd;

        const char *device = "/dev/input/js0";
        
        if (argc > 1) {
                device = argv[1];
        }

        fd = fopen(device, "r");
        if (fd == NULL) {
                int save_errno = errno;
                fprintf(stderr, "fopen(\"%s\")=%d %s\n", device, save_errno, strerror(save_errno));
                exit(EXIT_FAILURE);
        }

        int nbt = 0, nlc = 0;
        uint8_t maxbt = 0, maxlc = 0;
        int preamble = 1;

        for (;;) {
                char buf[8];
                uint32_t cnt;
                int16_t value;
                uint8_t type, idx;

                size_t rc;

                rc = fread((void *)&buf[0], 1, sizeof(buf), fd);
                if (rc < 1) {
                        fprintf(stderr, "fread returned no data\n");
                        break;
                }

                cnt = *((uint32_t *)&buf[0]);
                value = *((int16_t *)&buf[4]);
                type = *((uint8_t *)&buf[6]);
                idx = *((uint8_t *)&buf[7]);

                if (preamble) {
                        if (!(type & 0x80U)) {
                                printf("buttons=%d (max=%u) linear controls=%d (max=%u)\n\n", nbt, maxbt, nlc, maxlc);
                                preamble = 0;

                        } else {
                                switch (type & 0x7FU) {
                                case 1:
                                        nbt++;
                                        if (idx > maxbt) {
                                                maxbt = idx;
                                        }
                                        break;

                                case 2:
                                        nlc++;
                                        if (idx > maxlc) {
                                                maxlc = idx;
                                        }
                                        break;
                                }

                                printf("0x%8x %s[%2u]=%6d\n", cnt, type2str(type & 0x7FU), idx, value);

                                continue;
                        }
                }

                printf("0x%8x %s[%2u]=%6d\n", cnt, type2str(type), idx, value);
        }

        return 0;
}

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static const char* type2str ( uint8_t  type )

static

Definition at line 44 of file hid_detect.c.

Referenced by main().

{
        switch (type) {
        case 1:
                return "button";
        case 2:
                return "linctl";
        }
        return "unknwn";
}