From 3d461676a90eecf584dc07317cdb52eba96aa2d9 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Tue, 13 Nov 2007 22:22:29 +0000 Subject: [PATCH] tr: better comments, small code shrink function old new delta expand 2232 2230 -2 tr_main 677 655 -22 --- coreutils/tr.c | 107 +++++++++++++++++++++++++++---------------------- 1 file changed, 60 insertions(+), 47 deletions(-) diff --git a/coreutils/tr.c b/coreutils/tr.c index e60e08b25..f6f458bf0 100644 --- a/coreutils/tr.c +++ b/coreutils/tr.c @@ -42,19 +42,46 @@ static void map(char *pvector, } /* supported constructs: - * Ranges, e.g., [0-9] ==> 0123456789 - * Escapes, e.g., \a ==> Control-G - * Character classes, e.g. [:upper:] ==> A ... Z + * Ranges, e.g., 0-9 ==> 0123456789 + * Ranges, e.g., [0-9] ==> 0123456789 + * Escapes, e.g., \a ==> Control-G + * Character classes, e.g. [:upper:] ==> A...Z + * Equiv classess, e.g. [=A=] ==> A (hmmmmmmm?) */ static unsigned int expand(const char *arg, char *buffer) { char *buffer_start = buffer; - unsigned i; /* XXX: FIXME: use unsigned char? */ + unsigned i; /* can't be unsigned char: must be able to hold 256 */ unsigned char ac; + + while (*arg) { + if (*arg == '\\') { + arg++; + *buffer++ = bb_process_escape_sequence(&arg); + continue; + } + if (arg[1] == '-') { /* "0-9..." */ + ac = arg[2]; + if (ac == '\0') { /* "0-": copy verbatim */ + *buffer++ = *arg++; /* copy '0' */ + continue; /* next iter will copy '-' and stop */ + } + i = *arg; + while (i <= ac) /* ok: i is unsigned _int_ */ + *buffer++ = i++; + arg += 3; /* skip 0-9 */ + continue; + } + if (*arg == '[') { /* "[xyz..." */ + arg++; + i = *arg++; + /* "[xyz...", i=x, arg points to y */ + if (ENABLE_FEATURE_TR_CLASSES && i == ':') { #define CLO ":]\0" - static const char classes[] ALIGN1 = - "alpha"CLO "alnum"CLO "digit"CLO "lower"CLO "upper"CLO "space"CLO - "blank"CLO "punct"CLO "cntrl"CLO; + static const char classes[] ALIGN1 = + "alpha"CLO "alnum"CLO "digit"CLO + "lower"CLO "upper"CLO "space"CLO + "blank"CLO "punct"CLO "cntrl"CLO; #define CLASS_invalid 0 /* we increment the retval */ #define CLASS_alpha 1 #define CLASS_alnum 2 @@ -68,27 +95,9 @@ static unsigned int expand(const char *arg, char *buffer) //#define CLASS_xdigit 10 //#define CLASS_graph 11 //#define CLASS_print 12 - while (*arg) { - if (*arg == '\\') { - arg++; - *buffer++ = bb_process_escape_sequence(&arg); - } else if (*(arg+1) == '-') { - ac = *(arg+2); - if (ac == 0) { - *buffer++ = *arg++; - continue; - } - i = *arg; - while (i <= ac) - *buffer++ = i++; - arg += 3; /* Skip the assumed a-z */ - } else if (*arg == '[') { - arg++; - i = *arg++; - if (ENABLE_FEATURE_TR_CLASSES && i == ':') { smalluint j; { /* not really pretty.. */ - char *tmp = xstrndup(arg, 7); // warning: xdigit needs 8, not 7 + char *tmp = xstrndup(arg, 7); // warning: xdigit would need 8, not 7 j = index_in_strings(classes, tmp) + 1; free(tmp); } @@ -115,10 +124,9 @@ static unsigned int expand(const char *arg, char *buffer) *buffer++ = ' '; } if (j == CLASS_punct || j == CLASS_cntrl) { - for (i = 0; i <= ASCII; i++) - if ((j == CLASS_punct && - isprint(i) && (!isalnum(i)) && (!isspace(i))) || - (j == CLASS_cntrl && iscntrl(i))) + for (i = '\0'; i <= ASCII; i++) + if ((j == CLASS_punct && isprint(i) && !isalnum(i) && !isspace(i)) + || (j == CLASS_cntrl && iscntrl(i))) *buffer++ = i; } if (j == CLASS_invalid) { @@ -128,22 +136,26 @@ static unsigned int expand(const char *arg, char *buffer) } break; } - if (ENABLE_FEATURE_TR_EQUIV && i == '=') { - *buffer++ = *arg; - arg += 3; /* Skip the closing =] */ + /* "[xyz...", i=x, arg points to y */ + if (ENABLE_FEATURE_TR_EQUIV && i == '=') { /* [=CHAR=] */ + *buffer++ = *arg; /* copy CHAR */ + arg += 3; /* skip CHAR=] */ continue; } - if (*arg++ != '-') { + if (*arg != '-') { /* not [x-...] - copy verbatim */ *buffer++ = '['; - arg -= 2; - continue; + arg--; /* points to x */ + continue; /* copy all, including eventual ']' */ } + /* [x-y...] */ + arg++; ac = *arg++; while (i <= ac) *buffer++ = i++; - arg++; /* Skip the assumed ']' */ - } else - *buffer++ = *arg++; + arg++; /* skip the assumed ']' */ + continue; + } + *buffer++ = *arg++; } return (buffer - buffer_start); } @@ -154,7 +166,7 @@ static int complement(char *buffer, int buffer_len) char conv[ASCII + 2]; ix = 0; - for (i = 0; i <= ASCII; i++) { + for (i = '\0'; i <= ASCII; i++) { for (j = 0; j < buffer_len; j++) if (buffer[j] == i) break; @@ -174,7 +186,9 @@ int tr_main(int argc, char **argv) int i; smalluint flags = 0; ssize_t read_chars = 0; - size_t in_index = 0, out_index = 0, c, coded, last = -1; + size_t in_index = 0, out_index = 0; + unsigned last = UCHAR_MAX + 1; /* not equal to any char */ + unsigned char coded, c; RESERVE_CONFIG_UBUFFER(output, BUFSIZ); RESERVE_CONFIG_BUFFER(vector, ASCII+1); RESERVE_CONFIG_BUFFER(invec, ASCII+1); @@ -203,8 +217,8 @@ int tr_main(int argc, char **argv) input_length = expand(argv[idx++], tr_buf); if (flags & TR_OPT_complement) input_length = complement(tr_buf, input_length); - if (argv[idx] != NULL) { - if (*argv[idx] == '\0') + if (argv[idx]) { + if (argv[idx][0] == '\0') bb_error_msg_and_die("STRING2 cannot be empty"); output_length = expand(argv[idx], output); map(vector, tr_buf, input_length, output, output_length); @@ -222,9 +236,8 @@ int tr_main(int argc, char **argv) xwrite(STDOUT_FILENO, (char *)output, out_index); out_index = 0; } - read_chars = read(STDIN_FILENO, tr_buf, BUFSIZ); + read_chars = safe_read(STDIN_FILENO, tr_buf, BUFSIZ); if (read_chars <= 0) { - xwrite(STDOUT_FILENO, (char *)output, out_index); if (read_chars < 0) bb_perror_msg_and_die(bb_msg_read_error); exit(EXIT_SUCCESS); @@ -235,8 +248,8 @@ int tr_main(int argc, char **argv) coded = vector[c]; if ((flags & TR_OPT_delete) && invec[c]) continue; - if ((flags & TR_OPT_squeeze_reps) && last == coded && - (invec[c] || outvec[coded])) + if ((flags & TR_OPT_squeeze_reps) && last == coded + && (invec[c] || outvec[coded])) continue; output[out_index++] = last = coded; } -- 2.25.1