現在、interface(2019年１月号)を参考にultra96でyolov3の高速化をしています。dma_simple.hとdma_simple.cを含めてmakeを行うとwarningが出ました。

warning

./src/dma_simple.c: In function 'udmabuf_open':
./src/dma_simple.c:18:12: warning: pointer targets in passing argument 1 of 'sscanf' differ in signedness [-Wpointer-sign]
     sscanf(attr, "%x", &udmabuf->phys_addr);
            ^~~~
In file included from /usr/include/features.h:423:0,
                 from /usr/include/bits/libc-header-start.h:33,
                 from /usr/include/stdio.h:27,
                 from ./src/dma_simple.h:1,
                 from ./src/dma_simple.c:1:
/usr/include/stdio.h:400:12: note: expected 'const char * restrict' but argument is of type 'unsigned char *'
 extern int __REDIRECT_NTH (sscanf, (const char *__restrict __s,
            ^
./src/dma_simple.c:18:20: warning: format '%x' expects argument of type 'unsigned int *', but argument 3 has type 'long unsigned int *' [-Wformat=]
     sscanf(attr, "%x", &udmabuf->phys_addr);
                   ~^   ~~~~~~~~~~~~~~~~~~~
                   %lx
./src/dma_simple.c:27:12: warning: pointer targets in passing argument 1 of 'sscanf' differ in signedness [-Wpointer-sign]
     sscanf(attr, "%d", &udmabuf->buf_size);
            ^~~~
In file included from /usr/include/features.h:423:0,
                 from /usr/include/bits/libc-header-start.h:33,
                 from /usr/include/stdio.h:27,
                 from ./src/dma_simple.h:1,
                 from ./src/dma_simple.c:1:
/usr/include/stdio.h:400:12: note: expected 'const char * restrict' but argument is of type 'unsigned char *'
 extern int __REDIRECT_NTH (sscanf, (const char *__restrict __s,
            ^

おそらくudmabufの型の形が一致してないことでなっているかと思いますが、どこを修正すべきかわかりません。

dma_simple.h

struct udmabuf {
    char           name[128];
    int            file;
    unsigned char* buf;
    unsigned int   buf_size;
    unsigned long  phys_addr;
    unsigned long  debug_vma;
    unsigned long  sync_mode;
};

int udmabuf_open(struct udmabuf* udmabuf, const char* name);

int udmabuf_close(struct udmabuf* udmabuf);

dma_simple.c

#include "dma_simple.h"

int udmabuf_open(struct udmabuf* udmabuf, const char* name)
{
    char           file_name[1024];
    int            fd;
    unsigned char  attr[1024];

    strcpy(udmabuf->name, name);
    udmabuf->file = -1;

    sprintf(file_name, "/sys/class/udmabuf/%s/phys_addr", name);
    if ((fd  = open(file_name, O_RDONLY)) == -1) {
        printf("Can not open %s\n", file_name);
        return (-1);
    }
    read(fd, (void*)attr, 1024);
    sscanf(attr, "%x", &udmabuf->phys_addr);
    close(fd);

    sprintf(file_name, "/sys/class/udmabuf/%s/size", name);
    if ((fd  = open(file_name, O_RDONLY)) == -1) {
        printf("Can not open %s\n", file_name);
        return (-1);
    }
    read(fd, (void*)attr, 1024);
    sscanf(attr, "%d", &udmabuf->buf_size);
    close(fd);

    sprintf(file_name, "/dev/%s", name);
    if ((udmabuf->file = open(file_name, O_RDWR | O_SYNC)) == -1) {
        printf("Can not open %s\n", file_name);
        return (-1);
    }

    udmabuf->buf = mmap(NULL, udmabuf->buf_size, PROT_READ|PROT_WRITE, MAP_SHARED, udmabuf->file, 0);
    udmabuf->debug_vma = 0;
    udmabuf->sync_mode = 1;

    return 0;
}

int udmabuf_close(struct udmabuf* udmabuf)
{
    if (udmabuf->file < 0)
        return -1;

    close(udmabuf->file);
    udmabuf->file = -1;
    return 0;
}