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cut: stop using static data. This alone removed ~70 bytes of code.
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 + some optimizations

function                                             old     new   delta
nlists                                                 4       -      -4
cut_lists                                              4       -      -4
cut_main                                            1041     960     -81
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Denis Vlasenko committed Jul 22, 2008
1 parent a525403 commit 9e3a540
Showing 1 changed file with 30 additions and 23 deletions.
53 changes: 30 additions & 23 deletions coreutils/cut.c
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Original file line number Diff line number Diff line change
Expand Up @@ -33,46 +33,46 @@ enum {
NON_RANGE = -1
};

/* growable array holding a series of lists */
static struct cut_list *cut_lists;
static unsigned int nlists; /* number of elements in above list */


static int cmpfunc(const void *a, const void *b)
{
return (((struct cut_list *) a)->startpos -
((struct cut_list *) b)->startpos);

}

static void cut_file(FILE *file, char delim)
static void cut_file(FILE *file, char delim, const struct cut_list *cut_lists, unsigned nlists)
{
char *line = NULL;
unsigned int linenum = 0; /* keep these zero-based to be consistent */
char *line;
unsigned linenum = 0; /* keep these zero-based to be consistent */

/* go through every line in the file */
while ((line = xmalloc_fgetline(file)) != NULL) {

/* set up a list so we can keep track of what's been printed */
char * printed = xzalloc(strlen(line) * sizeof(char));
char * orig_line = line;
unsigned int cl_pos = 0;
int linelen = strlen(line);
char *printed = xzalloc(linelen * sizeof(char));
char *orig_line = line;
unsigned cl_pos = 0;
int spos;

/* cut based on chars/bytes XXX: only works when sizeof(char) == byte */
if (option_mask32 & (CUT_OPT_CHAR_FLGS | CUT_OPT_BYTE_FLGS)) {
/* print the chars specified in each cut list */
for (; cl_pos < nlists; cl_pos++) {
spos = cut_lists[cl_pos].startpos;
while (spos < (int)strlen(line)) {
while (spos < linelen) {
if (!printed[spos]) {
printed[spos] = 'X';
putchar(line[spos]);
}
spos++;
if (spos > cut_lists[cl_pos].endpos
|| cut_lists[cl_pos].endpos == NON_RANGE)
/* NON_RANGE is -1, so if below is true,
* the above was true too (spos is >= 0) */
/* || cut_lists[cl_pos].endpos == NON_RANGE */
) {
break;
}
}
}
} else if (delim == '\n') { /* cut by lines */
Expand All @@ -89,7 +89,8 @@ static void cut_file(FILE *file, char delim)
spos++;
/* go to the next list if we're at the end of this one */
if (spos > cut_lists[cl_pos].endpos
|| cut_lists[cl_pos].endpos == NON_RANGE) {
|| cut_lists[cl_pos].endpos == NON_RANGE
) {
cl_pos++;
/* get out if there's no more lists to process */
if (cl_pos >= nlists)
Expand Down Expand Up @@ -148,7 +149,7 @@ static void cut_file(FILE *file, char delim)
* this is a list, and we're not at the end of that
* list */
} while (spos <= cut_lists[cl_pos].endpos && line
&& cut_lists[cl_pos].endpos != NON_RANGE);
&& cut_lists[cl_pos].endpos != NON_RANGE);
}
}
/* if we printed anything at all, we need to finish it with a
Expand All @@ -164,28 +165,32 @@ static void cut_file(FILE *file, char delim)
int cut_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int cut_main(int argc UNUSED_PARAM, char **argv)
{
/* growable array holding a series of lists */
struct cut_list *cut_lists = NULL;
unsigned nlists = 0; /* number of elements in above list */
char delim = '\t'; /* delimiter, default is tab */
char *sopt, *ltok;
unsigned opt;

opt_complementary = "b--bcf:c--bcf:f--bcf";
getopt32(argv, optstring, &sopt, &sopt, &sopt, &ltok);
opt = getopt32(argv, optstring, &sopt, &sopt, &sopt, &ltok);
// argc -= optind;
argv += optind;
if (!(option_mask32 & (CUT_OPT_BYTE_FLGS | CUT_OPT_CHAR_FLGS | CUT_OPT_FIELDS_FLGS)))
if (!(opt & (CUT_OPT_BYTE_FLGS | CUT_OPT_CHAR_FLGS | CUT_OPT_FIELDS_FLGS)))
bb_error_msg_and_die("expected a list of bytes, characters, or fields");

if (option_mask32 & CUT_OPT_DELIM_FLGS) {
if (opt & CUT_OPT_DELIM_FLGS) {
if (ltok[0] && ltok[1]) { /* more than 1 char? */
bb_error_msg_and_die("the delimiter must be a single character");
}
delim = ltok[0];
}

/* non-field (char or byte) cutting has some special handling */
if (!(option_mask32 & CUT_OPT_FIELDS_FLGS)) {
if (!(opt & CUT_OPT_FIELDS_FLGS)) {
static const char _op_on_field[] ALIGN1 = " only when operating on fields";

if (option_mask32 & CUT_OPT_SUPPRESS_FLGS) {
if (opt & CUT_OPT_SUPPRESS_FLGS) {
bb_error_msg_and_die
("suppressing non-delimited lines makes sense%s",
_op_on_field);
Expand Down Expand Up @@ -231,8 +236,8 @@ int cut_main(int argc UNUSED_PARAM, char **argv)
e = EOL;
} else {
e = xatoi_u(ltok);
/* if the user specified and end position of 0, that means "til the
* end of the line */
/* if the user specified and end position of 0,
* that means "til the end of the line" */
if (e == 0)
e = EOL;
e--; /* again, arrays are zero based, lines are 1 based */
Expand All @@ -242,6 +247,8 @@ int cut_main(int argc UNUSED_PARAM, char **argv)

/* add the new list */
cut_lists = xrealloc_vector(cut_lists, 4, nlists);
/* NB: startpos is always >= 0,
* while endpos may be = NON_RANGE (-1) */
cut_lists[nlists].startpos = s;
cut_lists[nlists].endpos = e;
nlists++;
Expand Down Expand Up @@ -269,7 +276,7 @@ int cut_main(int argc UNUSED_PARAM, char **argv)
retval = EXIT_FAILURE;
continue;
}
cut_file(file, delim);
cut_file(file, delim, cut_lists, nlists);
fclose_if_not_stdin(file);
} while (*++argv);

Expand Down

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