dd: support conv=fsync
authorDenis Vlasenko <vda.linux@googlemail.com>
Wed, 2 Apr 2008 21:20:35 +0000 (21:20 -0000)
committerDenis Vlasenko <vda.linux@googlemail.com>
Wed, 2 Apr 2008 21:20:35 +0000 (21:20 -0000)
dd: support "dd --" if CONFIG_DESKTOP=y

function                                             old     new   delta
static.conv_words                                      -      28     +28
dd_main                                             1369    1373      +4
static.keywords                                      848     827     -21
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/1 up/down: 32/-21)             Total: 11 bytes

coreutils/dd.c

index f3330e624593779d6061d4630d3e790a10fcbe5e..e172b0c292182880b8935531eba9a15cec737df2 100644 (file)
@@ -79,23 +79,31 @@ static bool write_and_stats(const void *buf, size_t len, size_t obs,
 #endif
 
 int dd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int dd_main(int argc, char **argv)
+int dd_main(int argc ATTRIBUTE_UNUSED, char **argv)
 {
        enum {
-               FLAG_SYNC    = 1 << 0,
-               FLAG_NOERROR = 1 << 1,
-               FLAG_NOTRUNC = 1 << 2,
-               FLAG_TWOBUFS = 1 << 3,
-               FLAG_COUNT   = 1 << 4,
+               /* Must be in the same order as OP_conv_XXX! */
+               /* (see "flags |= (1 << what)" below) */
+               FLAG_NOTRUNC = 1 << 0,
+               FLAG_SYNC    = 1 << 1,
+               FLAG_NOERROR = 1 << 2,
+               FLAG_FSYNC   = 1 << 3,
+               /* end of conv flags */
+               FLAG_TWOBUFS = 1 << 4,
+               FLAG_COUNT   = 1 << 5,
        };
        static const char keywords[] ALIGN1 =
                "bs=\0""count=\0""seek=\0""skip=\0""if=\0""of=\0"
 #if ENABLE_FEATURE_DD_IBS_OBS
-               "ibs=\0""obs=\0""conv=\0""notrunc\0""sync\0""noerror\0"
+               "ibs=\0""obs=\0""conv=\0"
 #endif
                ;
+#if ENABLE_FEATURE_DD_IBS_OBS
+       static const char conv_words[] ALIGN1 =
+               "notrunc\0""sync\0""noerror\0""fsync\0";
+#endif
        enum {
-               OP_bs = 1,
+               OP_bs = 0,
                OP_count,
                OP_seek,
                OP_skip,
@@ -105,9 +113,23 @@ int dd_main(int argc, char **argv)
                OP_ibs,
                OP_obs,
                OP_conv,
-               OP_conv_notrunc,
+               /* Must be in the same order as FLAG_XXX! */
+               OP_conv_notrunc = 0,
                OP_conv_sync,
                OP_conv_noerror,
+               OP_conv_fsync,
+       /* Unimplemented conv=XXX: */
+       //nocreat       do not create the output file
+       //excl          fail if the output file already exists
+       //fdatasync     physically write output file data before finishing
+       //swab          swap every pair of input bytes
+       //lcase         change upper case to lower case
+       //ucase         change lower case to upper case
+       //block         pad newline-terminated records with spaces to cbs-size
+       //unblock       replace trailing spaces in cbs-size records with newline
+       //ascii         from EBCDIC to ASCII
+       //ebcdic        from ASCII to EBCDIC
+       //ibm           from ASCII to alternate EBCDIC
 #endif
        };
        int exitcode = EXIT_FAILURE;
@@ -138,85 +160,85 @@ int dd_main(int argc, char **argv)
        signal_SA_RESTART_empty_mask(SIGUSR1, dd_output_status);
 #endif
 
-       for (n = 1; n < argc; n++) {
-               smalluint key_len;
-               smalluint what;
-               char *key;
+       for (n = 1; argv[n]; n++) {
+               int what;
+               char *val;
                char *arg = argv[n];
 
-//XXX:FIXME: we reject plain "dd --" This would cost ~20 bytes, so..
-//if (*arg == '-' && *++arg == '-' && !*++arg) continue;
-               key = strstr(arg, "=");
-               if (key == NULL)
+#if ENABLE_DESKTOP
+               /* "dd --". NB: coreutils 6.9 will complain if they see
+                * more than one of them. We wouldn't. */
+               if (arg[0] == '-' && arg[1] == '-' && arg[2] == '\0')
+                       continue;
+#endif
+               val = strchr(arg, '=');
+               if (val == NULL)
                        bb_show_usage();
-               key_len = key - arg + 1;
-               key = xstrndup(arg, key_len);
-               what = index_in_strings(keywords, key) + 1;
-               if (ENABLE_FEATURE_CLEAN_UP)
-                       free(key);
-               if (what == 0)
+               *val = '\0';
+               what = index_in_strings(keywords, arg);
+               if (what < 0)
                        bb_show_usage();
-               arg += key_len;
+               /* *val = '='; - to preserve ps listing? */
+               val++;
 #if ENABLE_FEATURE_DD_IBS_OBS
                if (what == OP_ibs) {
                        /* Must fit into positive ssize_t */
-                       ibs = xatoul_range_sfx(arg, 1, ((size_t)-1L)/2, dd_suffixes);
-                       continue;
+                       ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
+                       /*continue;*/
                }
                if (what == OP_obs) {
-                       obs = xatoul_range_sfx(arg, 1, ((size_t)-1L)/2, dd_suffixes);
-                       continue;
+                       obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
+                       /*continue;*/
                }
                if (what == OP_conv) {
                        while (1) {
-                               /* find ',', replace them with NUL so we can use arg for
+                               /* find ',', replace them with NUL so we can use val for
                                 * index_in_strings() without copying.
-                                * We rely on arg being non-null, else strchr would fault.
+                                * We rely on val being non-null, else strchr would fault.
                                 */
-                               key = strchr(arg, ',');
-                               if (key)
-                                       *key = '\0';
-                               what = index_in_strings(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 |= FLAG_NOTRUNC;
-                               if (what == OP_conv_sync)
-                                       flags |= FLAG_SYNC;
-                               if (what == OP_conv_noerror)
-                                       flags |= FLAG_NOERROR;
-                               if (!key) /* no ',' left, so this was the last specifier */
+                               arg = strchr(val, ',');
+                               if (arg)
+                                       *arg = '\0';
+                               what = index_in_strings(conv_words, val);
+                               if (what < 0)
+                                       bb_error_msg_and_die(bb_msg_invalid_arg, val, "conv");
+                               flags |= (1 << what);
+                               if (!arg) /* no ',' left, so this was the last specifier */
                                        break;
-                               arg = key + 1; /* skip this keyword and ',' */
+                               /* *arg = ','; - to preserve ps listing? */
+                               val = arg + 1; /* skip this keyword and ',' */
                        }
-                       continue;
+                       continue; /* we trashed 'what', can't fall through */
                }
 #endif
                if (what == OP_bs) {
-                       ibs = obs = xatoul_range_sfx(arg, 1, ((size_t)-1L)/2, dd_suffixes);
-                       continue;
+                       ibs = obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
+                       /*continue;*/
                }
                /* These can be large: */
                if (what == OP_count) {
                        flags |= FLAG_COUNT;
-                       count = XATOU_SFX(arg, dd_suffixes);
-                       continue;
+                       count = XATOU_SFX(val, dd_suffixes);
+                       /*continue;*/
                }
                if (what == OP_seek) {
-                       seek = XATOU_SFX(arg, dd_suffixes);
-                       continue;
+                       seek = XATOU_SFX(val, dd_suffixes);
+                       /*continue;*/
                }
                if (what == OP_skip) {
-                       skip = XATOU_SFX(arg, dd_suffixes);
-                       continue;
+                       skip = XATOU_SFX(val, dd_suffixes);
+                       /*continue;*/
                }
                if (what == OP_if) {
-                       infile = arg;
-                       continue;
+                       infile = val;
+                       /*continue;*/
                }
-               if (what == OP_of)
-                       outfile = arg;
-       }
+               if (what == OP_of) {
+                       outfile = val;
+                       /*continue;*/
+               }
+       } /* end of "for (argv[n])" */
+
 //XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
        ibuf = obuf = xmalloc(ibs);
        if (ibs != obs) {
@@ -304,13 +326,17 @@ int dd_main(int argc, char **argv)
                        }
                } else if (write_and_stats(ibuf, n, obs, outfile))
                        goto out_status;
+
+               if (flags & FLAG_FSYNC) {
+                       if (fsync(ofd) < 0)
+                               goto die_outfile;
+               }
        }
 
        if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
                w = full_write_or_warn(obuf, oc, outfile);
                if (w < 0) goto out_status;
-               if (w > 0)
-                       G.out_part++;
+               if (w > 0) G.out_part++;
        }
        if (close(ifd) < 0) {
  die_infile: