dd: fix bugs: always assumed conv=sync, died on write errors

w/o perror and statictics. Several small improvements

1 files changed, 69 insertions, 50 deletions

diff --git a/coreutils/dd.c b/coreutils/dd.c
index 78d831525..c0df0b75c 100644
--- a/coreutils/dd.c
+++ b/coreutils/dd.c
@@ -35,15 +35,26 @@ static void dd_output_status(int ATTRIBUTE_UNUSED cur_signal)
                         out_full, out_part);
 }
 
+static ssize_t full_write_or_warn(int fd, const void *buf, size_t len,
+                const char* filename)
+{
+        ssize_t n = full_write(fd, buf, len);
+        if (n < 0)
+                bb_perror_msg("writing '%s'", filename);
+        return n;
+}
+
 int dd_main(int argc, char **argv)
 {
-#define sync_flag    (1<<0)
-#define noerror      (1<<1)
-#define trunc_flag   (1<<2)
-#define twobufs_flag (1<<3)
+        enum {
+                sync_flag    = 1 << 0,
+                noerror      = 1 << 1,
+                trunc_flag   = 1 << 2,
+                twobufs_flag = 1 << 3,
+        };
         int flags = trunc_flag;
         size_t oc = 0, ibs = 512, obs = 512;
-        ssize_t n;
+        ssize_t n, w;
         off_t seek = 0, skip = 0, count = OFF_T_MAX;
         int oflag, ifd, ofd;
         const char *infile = NULL, *outfile = NULL;
@@ -60,52 +71,53 @@ int dd_main(int argc, char **argv)
         }
 
         for (n = 1; n < argc; n++) {
+                char *arg = argv[n];
+                /* Must fit into positive ssize_t */
+                if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("ibs=", arg, 4))
+                        ibs = xatoul_range_sfx(arg+4, 0, ((size_t)-1L)/2, dd_suffixes);
+                else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("obs=", arg, 4))
+                        obs = xatoul_range_sfx(arg+4, 0, ((size_t)-1L)/2, dd_suffixes);
+                else if (!strncmp("bs=", arg, 3))
+                        ibs = obs = xatoul_range_sfx(arg+3, 0, ((size_t)-1L)/2, dd_suffixes);
                 // FIXME: make them capable of eating LARGE numbers
-                if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("ibs=", argv[n], 4)) {
-                        ibs = xatoul_sfx(argv[n]+4, dd_suffixes);
-                        flags |= twobufs_flag;
-                } else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("obs=", argv[n], 4)) {
-                        obs = xatoul_sfx(argv[n]+4, dd_suffixes);
-                        flags |= twobufs_flag;
-                } else if (!strncmp("bs=", argv[n], 3))
-                        ibs = obs = xatoul_sfx(argv[n]+3, dd_suffixes);
-                else if (!strncmp("count=", argv[n], 6))
-                        count = xatoul_sfx(argv[n]+6, dd_suffixes);
-                else if (!strncmp("seek=", argv[n], 5))
-                        seek = xatoul_sfx(argv[n]+5, dd_suffixes);
-                else if (!strncmp("skip=", argv[n], 5))
-                        skip = xatoul_sfx(argv[n]+5, dd_suffixes);
-                else if (!strncmp("if=", argv[n], 3))
-                        infile = argv[n]+3;
-                else if (!strncmp("of=", argv[n], 3))
-                        outfile = argv[n]+3;
-                else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("conv=", argv[n], 5)) {
-                        ibuf = argv[n]+5;
+                else if (!strncmp("count=", arg, 6))
+                        count = xatoul_sfx(arg+6, dd_suffixes);
+                else if (!strncmp("seek=", arg, 5))
+                        seek = xatoul_sfx(arg+5, dd_suffixes);
+                else if (!strncmp("skip=", arg, 5))
+                        skip = xatoul_sfx(arg+5, dd_suffixes);
+
+                else if (!strncmp("if=", arg, 3))
+                        infile = arg+3;
+                else if (!strncmp("of=", arg, 3))
+                        outfile = arg+3;
+                else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("conv=", arg, 5)) {
+                        arg += 5;
                         while (1) {
-                                if (!strncmp("notrunc", ibuf, 7)) {
+                                if (!strncmp("notrunc", arg, 7)) {
                                         flags &= ~trunc_flag;
-                                        ibuf += 7;
-                                } else if (!strncmp("sync", ibuf, 4)) {
+                                        arg += 7;
+                                } else if (!strncmp("sync", arg, 4)) {
                                         flags |= sync_flag;
-                                        ibuf += 4;
-                                } else if (!strncmp("noerror", ibuf, 7)) {
+                                        arg += 4;
+                                } else if (!strncmp("noerror", arg, 7)) {
                                         flags |= noerror;
-                                        ibuf += 7;
+                                        arg += 7;
                                 } else {
-                                        bb_error_msg_and_die(bb_msg_invalid_arg, argv[n]+5, "conv");
+                                        bb_error_msg_and_die(bb_msg_invalid_arg, arg, "conv");
                                 }
-                                if (ibuf[0] == '\0') break;
-                                if (ibuf[0] == ',') ibuf++;
+                                if (arg[0] == '\0') break;
+                                if (*arg++ != ',') bb_show_usage();
                         }
                 } else
                         bb_show_usage();
         }
-        ibuf = xmalloc(ibs);
 
-        if (flags & twobufs_flag)
+        ibuf = obuf = xmalloc(ibs);
+        if (ibs != obs) {
+                flags |= twobufs_flag;
                 obuf = xmalloc(obs);
-        else
-                obuf = ibuf;
+        }
 
         if (infile != NULL)
                 ifd = xopen(infile, O_RDONLY);
@@ -173,7 +185,7 @@ int dd_main(int argc, char **argv)
                         in_full++;
                 else {
                         in_part++;
-                        if (sync_flag) {
+                        if (flags & sync_flag) {
                                 memset(ibuf + n, '\0', ibs - n);
                                 n = ibs;
                         }
@@ -190,33 +202,40 @@ int dd_main(int argc, char **argv)
                                 tmp += d;
                                 oc += d;
                                 if (oc == obs) {
-                                        xwrite(ofd, obuf, obs);
-                                        out_full++;
+                                        w = full_write_or_warn(ofd, obuf, obs, outfile);
+                                        if (w < 0) goto out_status;
+                                        if (w == obs)
+                                                out_full++;
+                                        else if (w > 0)
+                                                out_part++;
                                         oc = 0;
                                 }
                         }
                 } else {
-                        xwrite(ofd, ibuf, n);
-                        if (n == ibs)
+                        w = full_write_or_warn(ofd, ibuf, n, outfile);
+                        if (w < 0) goto out_status;
+                        if (w == obs)
                                 out_full++;
-                        else
+                        else if (w > 0)
                                 out_part++;
                 }
         }
 
         if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
-                xwrite(ofd, obuf, oc);
-                out_part++;
+                w = full_write_or_warn(ofd, obuf, oc, outfile);
+                if (w < 0) goto out_status;
+                if (w > 0)
+                        out_part++;
         }
-        if (close (ifd) < 0) {
+        if (close(ifd) < 0) {
                 bb_perror_msg_and_die("%s", infile);
         }
 
-        if (close (ofd) < 0) {
-die_outfile:
+        if (close(ofd) < 0) {
+ die_outfile:
                 bb_perror_msg_and_die("%s", outfile);
         }
-
+ out_status:
         dd_output_status(0);
 
         return EXIT_SUCCESS;