diff options
| -rw-r--r-- | coreutils/Config.in | 12 | ||||
| -rw-r--r-- | coreutils/dd.c | 33 |
2 files changed, 37 insertions, 8 deletions
diff --git a/coreutils/Config.in b/coreutils/Config.in index 4eb3db052..6841ec96d 100644 --- a/coreutils/Config.in +++ b/coreutils/Config.in @@ -115,6 +115,18 @@ config CONFIG_DD by default) using specific input and output blocksizes, while optionally performing conversions on it. +config CONFIG_FEATURE_DD_SIGNAL_HANDLING + bool "Enable DD signal handling for status reporting" + default y + depends on CONFIG_DD + help + sending a SIGUSR1 signal to a running `dd' process makes it + print to standard error the number of records read and written + so far, then to resume copying. + + $ dd if=/dev/zero of=/dev/null& pid=$! $ kill -USR1 $pid; sleep 1; kill $pid + 10899206+0 records in 10899206+0 records out + config CONFIG_DF bool "df" default n diff --git a/coreutils/dd.c b/coreutils/dd.c index ce8bcc6a5..378e212de 100644 --- a/coreutils/dd.c +++ b/coreutils/dd.c @@ -15,9 +15,9 @@ #include <unistd.h> #include <string.h> #include <fcntl.h> +#include <signal.h> // For FEATURE_DD_SIGNAL_HANDLING #include "busybox.h" - static const struct suffix_mult dd_suffixes[] = { { "c", 1 }, { "w", 2 }, @@ -31,12 +31,20 @@ static const struct suffix_mult dd_suffixes[] = { { NULL, 0 } }; +static size_t out_full; +static size_t out_part; +static size_t in_full; +static size_t in_part; + +static void dd_output_status(int cur_signal) +{ + fprintf(stderr, "%ld+%ld records in\n%ld+%ld records out\n", + (long)in_full, (long)in_part, + (long)out_full, (long)out_part); +} + int dd_main(int argc, char **argv) { - size_t out_full = 0; - size_t out_part = 0; - size_t in_full = 0; - size_t in_part = 0; size_t count = -1; size_t bs = 512; ssize_t n; @@ -53,6 +61,17 @@ int dd_main(int argc, char **argv) const char *outfile = NULL; char *buf; + if (ENABLE_FEATURE_DD_SIGNAL_HANDLING) + { + struct sigaction sa; + + memset(&sa, 0, sizeof(sa)); + sa.sa_handler = dd_output_status; + sa.sa_flags = SA_RESTART; + sigemptyset(&sa.sa_mask); + sigaction(SIGUSR1, &sa, 0); + } + for (i = 1; i < argc; i++) { if (strncmp("bs=", argv[i], 3) == 0) bs = bb_xparse_number(argv[i]+3, dd_suffixes); @@ -180,9 +199,7 @@ int dd_main(int argc, char **argv) bb_perror_msg_and_die("%s", outfile); } - fprintf(stderr, "%ld+%ld records in\n%ld+%ld records out\n", - (long)in_full, (long)in_part, - (long)out_full, (long)out_part); + dd_output_status(0); return EXIT_SUCCESS; } |