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-rw-r--r--examples/sg_simple4.c238
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diff --git a/examples/sg_simple4.c b/examples/sg_simple4.c
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+#include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include "sg_lib.h"
+#include "sg_io_linux.h"
+
+/* This is a simple program executing a SCSI INQUIRY command and a
+ TEST UNIT READY command using the SCSI generic (sg) driver
+ This variant shows mmap-ed IO being used to read the data returned
+ by the INQUIRY command.
+
+* Copyright (C) 2001-2016 D. Gilbert
+* 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, or (at your option)
+* any later version.
+
+ Invocation: sg_simple4 [-x] <sg_device>
+
+ Version 1.02 (20160528)
+
+6 byte INQUIRY command:
+[0x12][ |lu][pg cde][res ][al len][cntrl ]
+
+6 byte TEST UNIT READY command:
+[0x00][ |lu][res ][res ][res ][res ]
+
+*/
+
+#ifndef SG_FLAG_MMAP_IO
+#define SG_FLAG_MMAP_IO 4
+#endif /* since /usr/include/scsi/sg.h doesn't know about this yet */
+
+#define INQ_REPLY_LEN 96
+#define INQ_CMD_LEN 6
+#define TUR_CMD_LEN 6
+
+#define EBUFF_SZ 256
+
+int main(int argc, char * argv[])
+{
+ int sg_fd, k, ok;
+ unsigned char inq_cdb[INQ_CMD_LEN] =
+ {0x12, 0, 0, 0, INQ_REPLY_LEN, 0};
+ unsigned char tur_cdb[TUR_CMD_LEN] =
+ {0x00, 0, 0, 0, 0, 0};
+ unsigned char * inqBuff;
+ unsigned char * inqBuff2;
+ sg_io_hdr_t io_hdr;
+ char * file_name = 0;
+ char ebuff[EBUFF_SZ];
+ unsigned char sense_buffer[32];
+ int do_extra = 0;
+
+ for (k = 1; k < argc; ++k) {
+ if (0 == memcmp("-x", argv[k], 2))
+ do_extra = 1;
+ else if (*argv[k] == '-') {
+ printf("Unrecognized switch: %s\n", argv[k]);
+ file_name = 0;
+ break;
+ }
+ else if (0 == file_name)
+ file_name = argv[k];
+ else {
+ printf("too many arguments\n");
+ file_name = 0;
+ break;
+ }
+ }
+ if (0 == file_name) {
+ printf("Usage: 'sg_simple4 [-x] <sg_device>'\n");
+ return 1;
+ }
+
+ /* N.B. An access mode of O_RDWR is required for some SCSI commands */
+ if ((sg_fd = open(file_name, O_RDWR)) < 0) {
+ snprintf(ebuff, EBUFF_SZ,
+ "sg_simple4: error opening file: %s", file_name);
+ perror(ebuff);
+ return 1;
+ }
+ /* Just to be safe, check we have a new sg device by trying an ioctl */
+ if ((ioctl(sg_fd, SG_GET_VERSION_NUM, &k) < 0) || (k < 30122)) {
+ printf("sg_simple4: %s needs sg driver version >= 3.1.22\n",
+ file_name);
+ close(sg_fd);
+ return 1;
+ }
+
+ /* since I know this program will only read from inqBuff then I use
+ PROT_READ rather than PROT_READ | PROT_WRITE */
+ inqBuff = (unsigned char *)mmap(NULL, 8000, PROT_READ | PROT_WRITE,
+ MAP_SHARED, sg_fd, 0);
+ if (MAP_FAILED == inqBuff) {
+ snprintf(ebuff, EBUFF_SZ, "sg_simple4: error using mmap() on "
+ "file: %s", file_name);
+ perror(ebuff);
+ return 1;
+ }
+ if (inqBuff[0])
+ printf("non-null char at inqBuff[0]\n");
+ if (inqBuff[5000])
+ printf("non-null char at inqBuff[5000]\n");
+
+ /* Prepare INQUIRY command */
+ memset(&io_hdr, 0, sizeof(sg_io_hdr_t));
+ io_hdr.interface_id = 'S';
+ io_hdr.cmd_len = sizeof(inq_cdb);
+ /* io_hdr.iovec_count = 0; */ /* memset takes care of this */
+ io_hdr.mx_sb_len = sizeof(sense_buffer);
+ io_hdr.dxfer_direction = SG_DXFER_FROM_DEV;
+ io_hdr.dxfer_len = INQ_REPLY_LEN;
+ /* io_hdr.dxferp = inqBuff; // ignored in mmap-ed IO */
+ io_hdr.cmdp = inq_cdb;
+ io_hdr.sbp = sense_buffer;
+ io_hdr.timeout = 20000; /* 20000 millisecs == 20 seconds */
+ io_hdr.flags = SG_FLAG_MMAP_IO;
+ /* io_hdr.pack_id = 0; */
+ /* io_hdr.usr_ptr = NULL; */
+
+ if (ioctl(sg_fd, SG_IO, &io_hdr) < 0) {
+ perror("sg_simple4: Inquiry SG_IO ioctl error");
+ close(sg_fd);
+ return 1;
+ }
+
+ /* now for the error processing */
+ ok = 0;
+ switch (sg_err_category3(&io_hdr)) {
+ case SG_LIB_CAT_CLEAN:
+ ok = 1;
+ break;
+ case SG_LIB_CAT_RECOVERED:
+ printf("Recovered error on INQUIRY, continuing\n");
+ ok = 1;
+ break;
+ default: /* won't bother decoding other categories */
+ sg_chk_n_print3("INQUIRY command error", &io_hdr, 1);
+ break;
+ }
+
+ if (ok) { /* output result if it is available */
+ char * p = (char *)inqBuff;
+ int f = (int)*(p + 7);
+ printf("Some of the INQUIRY command's results:\n");
+ printf(" %.8s %.16s %.4s ", p + 8, p + 16, p + 32);
+ printf("[wide=%d sync=%d cmdque=%d sftre=%d]\n",
+ !!(f & 0x20), !!(f & 0x10), !!(f & 2), !!(f & 1));
+ /* Extra info, not necessary to look at */
+ if (do_extra)
+ printf("INQUIRY duration=%u millisecs, resid=%d, msg_status=%d\n",
+ io_hdr.duration, io_hdr.resid, (int)io_hdr.msg_status);
+ }
+
+
+ /* Prepare TEST UNIT READY command */
+ memset(&io_hdr, 0, sizeof(sg_io_hdr_t));
+ io_hdr.interface_id = 'S';
+ io_hdr.cmd_len = sizeof(tur_cdb);
+ io_hdr.mx_sb_len = sizeof(sense_buffer);
+ io_hdr.dxfer_direction = SG_DXFER_NONE;
+ io_hdr.cmdp = tur_cdb;
+ io_hdr.sbp = sense_buffer;
+ io_hdr.timeout = 20000; /* 20000 millisecs == 20 seconds */
+
+ if (ioctl(sg_fd, SG_IO, &io_hdr) < 0) {
+ perror("sg_simple4: Test Unit Ready SG_IO ioctl error");
+ close(sg_fd);
+ return 1;
+ }
+
+ /* now for the error processing */
+ ok = 0;
+ switch (sg_err_category3(&io_hdr)) {
+ case SG_LIB_CAT_CLEAN:
+ ok = 1;
+ break;
+ case SG_LIB_CAT_RECOVERED:
+ printf("Recovered error on Test Unit Ready, continuing\n");
+ ok = 1;
+ break;
+ default: /* won't bother decoding other categories */
+ sg_chk_n_print3("Test Unit Ready command error", &io_hdr, 1);
+ break;
+ }
+
+ if (ok)
+ printf("Test Unit Ready successful so unit is ready!\n");
+ else
+ printf("Test Unit Ready failed so unit may _not_ be ready!\n");
+
+ if (do_extra)
+ printf("TEST UNIT READY duration=%u millisecs, resid=%d, "
+ "msg_status=%d\n",
+ io_hdr.duration, io_hdr.resid, (int)io_hdr.msg_status);
+
+ /* munmap(inqBuff, 8000); */
+ /* could call munmap(inqBuff, INQ_REPLY_LEN) here but following close()
+ causes this too happen anyway */
+#if 1
+ inqBuff2 = (unsigned char *)mmap(NULL, 8000, PROT_READ | PROT_WRITE,
+ MAP_SHARED, sg_fd, 0);
+ if (MAP_FAILED == inqBuff2) {
+ snprintf(ebuff, EBUFF_SZ, "sg_simple4: error using mmap() 2 on "
+ "file: %s", file_name);
+ perror(ebuff);
+ return 1;
+ }
+ if (inqBuff2[0])
+ printf("non-null char at inqBuff2[0]\n");
+ if (inqBuff2[5000])
+ printf("non-null char at inqBuff2[5000]\n");
+ {
+ pid_t pid;
+ pid = fork();
+ if (pid) {
+ inqBuff2[5000] = 33;
+ munmap(inqBuff, 8000);
+ sleep(3);
+ }
+ else {
+ inqBuff[5000] = 0xaa;
+ munmap(inqBuff, 8000);
+ sleep(1);
+ }
+ }
+#endif
+ close(sg_fd);
+ return 0;
+}
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