diff options
| -rw-r--r-- | toys/posix/strings.c | 73 |
1 files changed, 46 insertions, 27 deletions
diff --git a/toys/posix/strings.c b/toys/posix/strings.c index d2154e79..911fc452 100644 --- a/toys/posix/strings.c +++ b/toys/posix/strings.c @@ -3,23 +3,29 @@ * Copyright 2014 Kyung-su Kim <kaspyx@gmail.com> * Copyright 2014 Kyungwan Han <asura321@gmail.com> * - * No Standard + * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/strings.html + * + * Deviations from posix: we don't readahead to the end of the string to see + * if it ends with NUL or newline before printing. Add -o. We always do -a + * (and accept but don't document the flag), but that's sort of conformant. + * Posix' STDOUT section says things like "%o %s" and we support 64 bit offsets. + * * TODO: utf8 strings - * TODO: posix -t -USE_STRINGS(NEWTOY(strings, "an#=4<1fo", TOYFLAG_USR|TOYFLAG_BIN)) +USE_STRINGS(NEWTOY(strings, "t:an#=4<1fo", TOYFLAG_USR|TOYFLAG_BIN)) config STRINGS bool "strings" default y help - usage: strings [-fo] [-n LEN] [FILE...] + usage: strings [-fo] [-t oxd] [-n LEN] [FILE...] Display printable strings in a binary file - -f Precede strings with filenames + -f Show filename -n At least LEN characters form a string (default 4) - -o Precede strings with decimal offsets + -o Show offset (ala -t d) + -t Show offset type (o=octal, d=decimal, x=hexadecimal) */ #define FOR_strings @@ -27,38 +33,51 @@ config STRINGS GLOBALS( long num; + char *t; ) static void do_strings(int fd, char *filename) { int nread, i, wlen = TT.num, count = 0; off_t offset = 0; - char *string = xzalloc(wlen + 1); + char *string = 0, pattern[8]; + + if (TT.t) if (!(string = strchr("oxd", *TT.t))) error_exit("-t needs oxd"); + sprintf(pattern, "%%7ll%c ", string ? *string : 'd'); - for (;;) { - nread = read(fd, toybuf, sizeof(toybuf)); - if (nread < 0) perror_msg_raw(filename); - if (nread < 1) { - if (count == wlen) xputc('\n'); - break; + // input buffer can wrap before we have enough data to output, so + // copy start of string to temporary buffer until enough to output + string = xzalloc(wlen+1); + + for (i = nread = 0; ;i++) { + if (i >= nread) { + nread = read(fd, toybuf, sizeof(toybuf)); + i = 0; + if (nread < 0) perror_msg_raw(filename); + if (nread < 1) { + if (count) goto flush; + break; + } } - for (i = 0; i < nread; i++, offset++) { - if (((toybuf[i] >= 32) && (toybuf[i] <= 126)) || (toybuf[i] == '\t')) { - if (count == wlen) fputc(toybuf[i], stdout); - else { - string[count++] = toybuf[i]; - if (count == wlen) { - if (toys.optflags & FLAG_f) printf("%s: ", filename); - if (toys.optflags & FLAG_o) - printf("%7lld ",(long long)(offset + 1 - wlen)); - printf("%s", string); - } + + offset++; + if ((toybuf[i]>=32 && toybuf[i]<=126) || toybuf[i]=='\t') { + if (count == wlen) fputc(toybuf[i], stdout); + else { + string[count++] = toybuf[i]; + if (count == wlen) { + if (toys.optflags & FLAG_f) printf("%s: ", filename); + if (toys.optflags & (FLAG_o|FLAG_t)) + printf(pattern, (long long)(offset - wlen)); + printf("%s", string); } - } else { - if (count == wlen) xputc('\n'); - count = 0; } + continue; } +flush: + // End of previous string + if (count == wlen) xputc('\n'); + count = 0; } xclose(fd); free(string); |