dd: fix a bug where we don't report write errors

testsuite: small cleanup

full_write_or_warn                                    38      40      +2
write_and_stats                                       66      67      +1
dd_main                                             1358    1335     -23
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 3/-23)             Total: -20 bytes

1 files changed, 22 insertions, 19 deletions

diff --git a/coreutils/dd.c b/coreutils/dd.c
index fd4e7e8a2..7552c8518 100644
--- a/coreutils/dd.c
+++ b/coreutils/dd.c
@@ -14,6 +14,11 @@
 /* This is a NOEXEC applet. Be very careful! */
 
 
+enum {
+        ifd = STDIN_FILENO,
+        ofd = STDOUT_FILENO,
+};
+
 static const struct suffix_mult dd_suffixes[] = {
         { "c", 1 },
         { "w", 2 },
@@ -45,19 +50,19 @@ static void dd_output_status(int ATTRIBUTE_UNUSED cur_signal)
                         G.out_full, G.out_part);
 }
 
-static ssize_t full_write_or_warn(int fd, const void *buf, size_t len,
+static ssize_t full_write_or_warn(const void *buf, size_t len,
         const char *const filename)
 {
-        ssize_t n = full_write(fd, buf, len);
+        ssize_t n = full_write(ofd, buf, len);
         if (n < 0)
                 bb_perror_msg("writing '%s'", filename);
         return n;
 }
 
-static bool write_and_stats(int fd, const void *buf, size_t len, size_t obs,
+static bool write_and_stats(const void *buf, size_t len, size_t obs,
         const char *filename)
 {
-        ssize_t n = full_write_or_warn(fd, buf, len, filename);
+        ssize_t n = full_write_or_warn(buf, len, filename);
         if (n < 0)
                 return 1;
         if (n == obs)
@@ -105,13 +110,13 @@ int dd_main(int argc, char **argv)
                 OP_conv_noerror,
 #endif
         };
+        int exitcode = EXIT_FAILURE;
         size_t ibs = 512, obs = 512;
         ssize_t n, w;
         char *ibuf, *obuf;
         /* And these are all zeroed at once! */
         struct {
                 int flags;
-                int ifd, ofd;
                 size_t oc;
                 off_t count;
                 off_t seek, skip;
@@ -121,8 +126,6 @@ int dd_main(int argc, char **argv)
 #endif
         } Z;
 #define flags   (Z.flags  )
-#define ifd     (Z.ifd    )
-#define ofd     (Z.ofd    )
 #define oc      (Z.oc     )
 #define count   (Z.count  )
 #define seek    (Z.seek   )
@@ -133,6 +136,7 @@ int dd_main(int argc, char **argv)
 
         memset(&Z, 0, sizeof(Z));
         INIT_G();
+        //fflush(NULL); - is this needed because of NOEXEC?
 
 #if ENABLE_FEATURE_DD_SIGNAL_HANDLING
         sigact.sa_handler = dd_output_status;
@@ -227,9 +231,8 @@ int dd_main(int argc, char **argv)
                 obuf = xmalloc(obs);
         }
         if (infile != NULL)
-                ifd = xopen(infile, O_RDONLY);
+                xmove_fd(xopen(infile, O_RDONLY), ifd);
         else {
-                /* ifd = STDIN_FILENO; - it's zero and it's already there */
                 infile = bb_msg_standard_input;
         }
         if (outfile != NULL) {
@@ -238,7 +241,7 @@ int dd_main(int argc, char **argv)
                 if (!seek && !(flags & FLAG_NOTRUNC))
                         oflag |= O_TRUNC;
 
-                ofd = xopen(outfile, oflag);
+                xmove_fd(xopen(outfile, oflag), ofd);
 
                 if (seek && !(flags & FLAG_NOTRUNC)) {
                         if (ftruncate(ofd, seek * obs) < 0) {
@@ -250,7 +253,6 @@ int dd_main(int argc, char **argv)
                         }
                 }
         } else {
-                ofd = STDOUT_FILENO;
                 outfile = bb_msg_standard_output;
         }
         if (skip) {
@@ -276,11 +278,10 @@ int dd_main(int argc, char **argv)
                 if (n == 0)
                         break;
                 if (n < 0) {
-                        if (flags & FLAG_NOERROR) {
-                                n = ibs;
-                                bb_simple_perror_msg(infile);
-                        } else
+                        if (!(flags & FLAG_NOERROR))
                                 goto die_infile;
+                        n = ibs;
+                        bb_simple_perror_msg(infile);
                 }
                 if ((size_t)n == ibs)
                         G.in_full++;
@@ -303,17 +304,17 @@ int dd_main(int argc, char **argv)
                                 tmp += d;
                                 oc += d;
                                 if (oc == obs) {
-                                        if (write_and_stats(ofd, obuf, obs, obs, outfile))
+                                        if (write_and_stats(obuf, obs, obs, outfile))
                                                 goto out_status;
                                         oc = 0;
                                 }
                         }
-                } else if (write_and_stats(ofd, ibuf, n, obs, outfile))
+                } else if (write_and_stats(ibuf, n, obs, outfile))
                         goto out_status;
         }
 
         if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
-                w = full_write_or_warn(ofd, obuf, oc, outfile);
+                w = full_write_or_warn(obuf, oc, outfile);
                 if (w < 0) goto out_status;
                 if (w > 0)
                         G.out_part++;
@@ -327,8 +328,10 @@ int dd_main(int argc, char **argv)
  die_outfile:
                 bb_simple_perror_msg_and_die(outfile);
         }
+
+        exitcode = EXIT_SUCCESS;
  out_status:
         dd_output_status(0);
 
-        return EXIT_SUCCESS;
+        return exitcode;
 }