toolbox: ioctl: fix signedness on ioctl_nr

ioctl_nr is passed signed to the kernel, but many users refer
to ioctl's in unsigned 32 bit notation.

Let's use stroll to set it, to let people specify either
negative numbers or large positive numbers.

Also improve error reporting.

Reported-By: Alex Piliev <ktnr74@motorola.com>
Change-Id: I789434895b70b051d4d5c1a5db566a1925478ef0

1 files changed, 96 insertions, 49 deletions

diff --git a/toolbox/ioctl.c b/toolbox/ioctl.c
index d1cc14a..093e467 100644
--- a/toolbox/ioctl.c
+++ b/toolbox/ioctl.c
@@ -1,36 +1,81 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdint.h>
+/*
+ * Copyright (c) 2008, The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *  * Neither the name of Google, Inc. nor the names of its contributors
+ *    may be used to endorse or promote products derived from this
+ *    software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <errno.h>
+#include <error.h>
 #include <fcntl.h>
 #include <getopt.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
 #include <string.h>
-#include <linux/kd.h>
-#include <linux/vt.h>
-#include <errno.h>
-#include <pthread.h>
 #include <sys/ioctl.h>
 #include <unistd.h>
 
-int ioctl_main(int argc, char *argv[])
-{
-    int c;
-    int fd;
-    int res;
+static void usage() {
+    fprintf(stderr, "%s [-l <length>] [-a <argsize>] [-rdh] <device> <ioctlnr>\n"
+            "  -l <length>   Length of io buffer\n"
+            "  -a <argsize>  Size of each argument (1-8)\n"
+            "  -r            Open device in read only mode\n"
+            "  -d            Direct argument (no iobuffer)\n"
+            "  -h            Print help\n", getprogname());
+    exit(1);
+}
+
+static int xstrtoi(const char* s, const char* what) {
+    char* endp;
+    errno = 0;
+    long result = strtol(s, &endp, 0);
+    if (errno != 0 || *endp != '\0') {
+        error(1, errno, "couldn't parse %s '%s'", what, s);
+    }
+    if (result > INT_MAX || result < INT_MIN) {
+        error(1, errno, "%s '%s' out of range", what, s);
+    }
+    return result;
+}
 
+int ioctl_main(int argc, char* argv[]) {
     int read_only = 0;
     int length = -1;
     int arg_size = 4;
     int direct_arg = 0;
-    uint32_t ioctl_nr;
+
     void *ioctl_args = NULL;
     uint8_t *ioctl_argp;
     uint8_t *ioctl_argp_save = NULL;
     int rem;
 
-    do {
-        c = getopt(argc, argv, "rdl:a:h");
-        if (c == EOF)
-            break;
+    int c;
+    while ((c = getopt(argc, argv, "rdl:a:h")) != -1) {
         switch (c) {
         case 'r':
             read_only = 1;
@@ -39,43 +84,44 @@ int ioctl_main(int argc, char *argv[])
             direct_arg = 1;
             break;
         case 'l':
-            length = strtol(optarg, NULL, 0);
+            length = xstrtoi(optarg, "length");
             break;
         case 'a':
-            arg_size = strtol(optarg, NULL, 0);
+            arg_size = xstrtoi(optarg, "argument size");
             break;
         case 'h':
-            fprintf(stderr, "%s [-l <length>] [-a <argsize>] [-rdh] <device> <ioctlnr>\n"
-                    "  -l <length>   Length of io buffer\n"
-                    "  -a <argsize>  Size of each argument (1-8)\n"
-                    "  -r            Open device in read only mode\n"
-                    "  -d            Direct argument (no iobuffer)\n"
-                    "  -h            Print help\n", argv[0]);
-            return -1;
-        case '?':
-            fprintf(stderr, "%s: invalid option -%c\n",
-                argv[0], optopt);
-            exit(1);
+            usage();
+            break;
+        default:
+            error(1, 0, "invalid option -%c", optopt);
         }
-    } while (1);
+    }
 
-    if(optind + 2 > argc) {
-        fprintf(stderr, "%s: too few arguments\n", argv[0]);
-        exit(1);
+    if (optind + 2 > argc) {
+        usage();
     }
 
-    if (!strcmp(argv[optind], "-")) {
+    const char* device = argv[optind];
+    int fd;
+    if (strcmp(device, "-") == 0) {
         fd = STDIN_FILENO;
     } else {
-        fd = open(argv[optind], read_only ? O_RDONLY : (O_RDWR | O_SYNC));
-        if (fd < 0) {
-            fprintf(stderr, "cannot open %s\n", argv[optind]);
-            return 1;
+        fd = open(device, read_only ? O_RDONLY : (O_RDWR | O_SYNC));
+        if (fd == -1) {
+            error(1, errno, "cannot open %s", argv[optind]);
         }
     }
     optind++;
-    
-    ioctl_nr = strtol(argv[optind], NULL, 0);
+
+    // IOCTL(2) wants second parameter as a signed int.
+    // Let's let the user specify either negative numbers or large positive
+    // numbers, for the case where ioctl number is larger than INT_MAX.
+    errno = 0;
+    char* endp;
+    int ioctl_nr = UINT_MAX & strtoll(argv[optind], &endp, 0);
+    if (errno != 0 || *endp != '\0') {
+        error(1, errno, "couldn't parse ioctl number '%s'", argv[optind]);
+    }
     optind++;
 
     if(direct_arg) {
@@ -91,11 +137,10 @@ int ioctl_main(int argc, char *argv[])
 
         ioctl_argp_save = ioctl_argp = ioctl_args;
         rem = length;
-        while(optind < argc) {
+        while (optind < argc) {
             uint64_t tmp = strtoull(argv[optind], NULL, 0);
-            if(rem < arg_size) {
-                fprintf(stderr, "%s: too many arguments\n", argv[0]);
-                exit(1);
+            if (rem < arg_size) {
+                error(1, 0, "too many arguments");
             }
             memcpy(ioctl_argp, &tmp, arg_size);
             ioctl_argp += arg_size;
@@ -108,8 +153,9 @@ int ioctl_main(int argc, char *argv[])
     while(rem--) {
         printf(" 0x%02x", *ioctl_argp_save++);
     }
-    printf("\n");
+    printf(" to %s\n", device);
 
+    int res;
     if(direct_arg)
         res = ioctl(fd, ioctl_nr, *(uint32_t*)ioctl_args);
     else if(length)
@@ -118,10 +164,10 @@ int ioctl_main(int argc, char *argv[])
         res = ioctl(fd, ioctl_nr, 0);
     if (res < 0) {
         free(ioctl_args);
-        fprintf(stderr, "ioctl 0x%x failed, %d\n", ioctl_nr, res);
-        return 1;
+        error(1, errno, "ioctl 0x%x failed (returned %d)", ioctl_nr, res);
     }
-    if(length) {
+
+    if (length) {
         printf("return buf:");
         ioctl_argp = ioctl_args;
         rem = length;
@@ -131,5 +177,6 @@ int ioctl_main(int argc, char *argv[])
         printf("\n");
     }
     free(ioctl_args);
+    close(fd);
     return 0;
 }