dd: fix skip= parse error (spotted by Dirk Clemens <develop@cle-mens.de>)

1 files changed, 24 insertions, 25 deletions

diff --git a/coreutils/dd.c b/coreutils/dd.c
index 8b374aa8b..797aabdd9 100644
--- a/coreutils/dd.c
+++ b/coreutils/dd.c
@@ -58,7 +58,7 @@ static bool write_and_stats(int fd, const void *buf, size_t len, size_t obs,
                 return 1;
         if (n == obs)
                 G.out_full++;
-        else if (n > 0)
+        else if (n) /* > 0 */
                 G.out_part++;
         return 0;
 }
@@ -73,10 +73,10 @@ int dd_main(int argc, char **argv);
 int dd_main(int argc, char **argv)
 {
         enum {
-                sync_flag    = 1 << 0,
-                noerror      = 1 << 1,
-                trunc_flag   = 1 << 2,
-                twobufs_flag = 1 << 3,
+                SYNC_FLAG    = 1 << 0,
+                NOERROR      = 1 << 1,
+                TRUNC_FLAG   = 1 << 2,
+                TWOBUFS_FLAG = 1 << 3,
         };
         static const char * const keywords[] = {
                 "bs=", "count=", "seek=", "skip=", "if=", "of=",
@@ -98,10 +98,10 @@ int dd_main(int argc, char **argv)
                 OP_conv,
                 OP_conv_notrunc,
                 OP_conv_sync,
-                OP_conv_noerror,
+                OP_conv_NOERROR,
 #endif
         };
-        int flags = trunc_flag;
+        int flags = TRUNC_FLAG;
         size_t oc = 0, ibs = 512, obs = 512;
         ssize_t n, w;
         off_t seek = 0, skip = 0, count = OFF_T_MAX;
@@ -152,23 +152,23 @@ int dd_main(int argc, char **argv)
                                 while (1) {
                                         /* find ',', replace them with nil so we can use arg for
                                          * index_in_str_array without copying.
-                                         * We rely on arg being non-null, else strstr would fault.
+                                         * We rely on arg being non-null, else strchr would fault.
                                          */
-                                        key = strstr(arg, ",");
+                                        key = strchr(arg, ',');
                                         if (key)
                                                 *key = '\0';
                                         what = index_in_str_array(keywords, arg) + 1;
                                         if (what < OP_conv_notrunc)
                                                 bb_error_msg_and_die(bb_msg_invalid_arg, arg, "conv");
                                         if (what == OP_conv_notrunc)
-                                                flags &= ~trunc_flag;
+                                                flags &= ~TRUNC_FLAG;
                                         if (what == OP_conv_sync)
-                                                flags |= sync_flag;
-                                        if (what == OP_conv_noerror)
-                                                flags |= noerror;
+                                                flags |= SYNC_FLAG;
+                                        if (what == OP_conv_NOERROR)
+                                                flags |= NOERROR;
                                         if (!key) /* no ',' left, so this was the last specifier */
                                                 break;
-                                        arg += key - arg + 1; /* skip this keyword plus ',' */
+                                        arg = key + 1; /* skip this keyword and ',' */
                                 }
                                 continue;
                         }
@@ -186,7 +186,7 @@ int dd_main(int argc, char **argv)
                         seek = XATOU_SFX(arg, dd_suffixes);
                         continue;
                 }
-                if (what == skip) {
+                if (what == OP_skip) {
                         skip = XATOU_SFX(arg, dd_suffixes);
                         continue;
                 }
@@ -200,7 +200,7 @@ int dd_main(int argc, char **argv)
 //XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
         ibuf = obuf = xmalloc(ibs);
         if (ibs != obs) {
-                flags |= twobufs_flag;
+                flags |= TWOBUFS_FLAG;
                 obuf = xmalloc(obs);
         }
         if (infile != NULL)
@@ -212,12 +212,12 @@ int dd_main(int argc, char **argv)
         if (outfile != NULL) {
                 int oflag = O_WRONLY | O_CREAT;
 
-                if (!seek && (flags & trunc_flag))
+                if (!seek && (flags & TRUNC_FLAG))
                         oflag |= O_TRUNC;
 
                 ofd = xopen(outfile, oflag);
 
-                if (seek && (flags & trunc_flag)) {
+                if (seek && (flags & TRUNC_FLAG)) {
                         if (ftruncate(ofd, seek * obs) < 0) {
                                 struct stat st;
 
@@ -247,13 +247,13 @@ int dd_main(int argc, char **argv)
         }
 
         while (G.in_full + G.in_part != count) {
-                if (flags & noerror) /* Pre-zero the buffer when for noerror */
+                if (flags & NOERROR) /* Pre-zero the buffer when for NOERROR */
                         memset(ibuf, '\0', ibs);
                 n = safe_read(ifd, ibuf, ibs);
                 if (n == 0)
                         break;
                 if (n < 0) {
-                        if (flags & noerror) {
+                        if (flags & NOERROR) {
                                 n = ibs;
                                 bb_perror_msg("%s", infile);
                         } else
@@ -263,12 +263,12 @@ int dd_main(int argc, char **argv)
                         G.in_full++;
                 else {
                         G.in_part++;
-                        if (flags & sync_flag) {
+                        if (flags & SYNC_FLAG) {
                                 memset(ibuf + n, '\0', ibs - n);
                                 n = ibs;
                         }
                 }
-                if (flags & twobufs_flag) {
+                if (flags & TWOBUFS_FLAG) {
                         char *tmp = ibuf;
                         while (n) {
                                 size_t d = obs - oc;
@@ -285,9 +285,8 @@ int dd_main(int argc, char **argv)
                                         oc = 0;
                                 }
                         }
-                } else
-                        if (write_and_stats(ofd, ibuf, n, obs, outfile))
-                                goto out_status;
+                } else if (write_and_stats(ofd, ibuf, n, obs, outfile))
+                        goto out_status;
         }
 
         if (ENABLE_FEATURE_DD_IBS_OBS && oc) {