sort: add -k, fix -u

Options  that are  specific to  a  single  key  definition are not
supported (e.g. "sort -k 2,3n -k 4,4").  Should you try to specify
such definitions, sort will  return with EXIT_FAILURE and an error
message.   Instead, all key definitions exclusively use the global
settings.

It always behaves like -b was set.
This commit is contained in:
Jakob Kramer 2014-04-12 17:53:10 +02:00 committed by sin
parent 02d91696b4
commit 98a12cc146
2 changed files with 178 additions and 14 deletions

19
sort.1
View File

@ -4,6 +4,9 @@ sort \- sort lines
.SH SYNOPSIS
.B sort
.RB [ \-nru ]
.RB [ \-k
.I key
.R ]...
.RI [ file ...]
.SH DESCRIPTION
.B sort
@ -18,4 +21,18 @@ perform a numeric sort.
reverses the sort.
.TP
.B \-u
prints repeated lines only once.
prints equal lines only once.
.TP
.B \-k key
specifies a key definition of the form \fBS\fR[.\fBs\fR][,\fBE\fR[.\fBe\fR]],
where
.B S,
.B s,
.B E,
and
.B e
are the starting column, starting character in that column, ending column and
the ending character of that column respectively. If they are not specified,
s refers to the first character of the specified starting column, E refers to
the last column of every line, and e refers to the last character of that last
column.

173
sort.c
View File

@ -1,4 +1,5 @@
/* See LICENSE file for copyright and license details. */
#include <ctype.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
@ -7,7 +8,28 @@
#include "text.h"
#include "util.h"
struct keydef {
unsigned start_column;
unsigned end_column;
unsigned start_char;
unsigned end_char;
};
struct kdlist {
struct keydef keydef;
struct kdlist *next;
};
static struct kdlist *head = NULL;
static struct kdlist *curr = NULL;
static void addkeydef(char *);
static void freelist(void);
static int linecmp(const char **, const char **);
static char *next_nonblank(char *);
static char *next_blank(char *);
static int parse_keydef(struct keydef *, char *);
static char *columns(char *, const struct keydef *);
static bool rflag = false;
static bool uflag = false;
@ -18,7 +40,7 @@ static struct linebuf linebuf = EMPTY_LINEBUF;
static void
usage(void)
{
eprintf("usage: %s [-nru] [file...]\n", argv0);
enprintf(2, "usage: %s [-nru] [-k def]... [file...]\n", argv0);
}
int
@ -37,15 +59,20 @@ main(int argc, char *argv[])
case 'u':
uflag = true;
break;
case 'k':
addkeydef(EARGF(usage()));
break;
default:
usage();
} ARGEND;
addkeydef("1");
if(argc == 0) {
getlines(stdin, &linebuf);
} else for(; argc > 0; argc--, argv++) {
if(!(fp = fopen(argv[0], "r"))) {
weprintf("fopen %s:", argv[0]);
enprintf(2, "fopen %s:", argv[0]);
continue;
}
getlines(fp, &linebuf);
@ -55,24 +82,144 @@ main(int argc, char *argv[])
(int (*)(const void *, const void *))linecmp);
for(i = 0; i < linebuf.nlines; i++) {
if(!uflag || i == 0 || strcmp(linebuf.lines[i],
linebuf.lines[i-1]) != 0) {
if(!uflag || i == 0 || linecmp((const char **)&linebuf.lines[i],
(const char **)&linebuf.lines[i-1])) {
fputs(linebuf.lines[i], stdout);
}
}
freelist();
return EXIT_SUCCESS;
}
int
linecmp(const char **a, const char **b)
static void
addkeydef(char *def)
{
if (nflag) {
if (rflag)
return strtoul(*b, 0, 10) - strtoul(*a, 0, 10);
else
return strtoul(*a, 0, 10) - strtoul(*b, 0, 10);
}
return strcmp(*a, *b) * (rflag ? -1 : +1);
struct kdlist *node;
node = malloc(sizeof(*node));
if(!node)
enprintf(2, "malloc:");
if(!head)
head = node;
if(parse_keydef(&node->keydef, def))
enprintf(2, "parse_keydef:");
if(curr)
curr->next = node;
node->next = NULL;
curr = node;
}
static void
freelist(void)
{
struct kdlist *node;
struct kdlist *tmp;
for(node = head; node; node = tmp) {
tmp = node->next;
free(node);
}
}
static int
linecmp(const char **a, const char **b)
{
char *s1, *s2;
int res = 0;
struct kdlist *node;
for(node = head; node && res == 0; node = node->next) {
s1 = columns((char *)*a, &node->keydef);
s2 = columns((char *)*b, &node->keydef);
/* don't consider modifiers if it's the default key
* definition that was implicitly added */
/* if -u is given, don't use default */
if(uflag && !(node == head) && !node->next)
res = 0;
else if(!(node == head) && !node->next)
res = strcmp(s1, s2);
else if(nflag)
res = strtoul(s1, 0, 10) - strtoul(s2, 0, 10);
else
res = strcmp(s1, s2);
free(s1);
free(s2);
}
return rflag ? -res : res;
}
static int
parse_keydef(struct keydef *kd, char *s)
{
char *rest = s;
kd->start_column = 1;
kd->start_char = 1;
/* 0 means end of line */
kd->end_column = 0;
kd->end_char = 0;
kd->start_column = strtoul(rest, &rest, 10);
if(!kd->start_column)
enprintf(2, "starting column cannot be 0\n");
if(*rest == '.')
kd->start_char = strtoul(rest+1, &rest, 10);
if(*rest == ',') {
kd->end_column = strtoul(rest+1, &rest, 10);
if(kd->end_column < kd->start_column)
enprintf(2, ",%u is too small\n", kd->end_column);
}
if(*rest == '.')
kd->end_char = strtoul(rest+1, &rest, 10);
if(*rest != '\0')
return -1;
return 0;
}
static char *
next_nonblank(char *s)
{
for(; *s && isblank(*s); s++);
return s;
}
static char *
next_blank(char *s)
{
for(; *s && !isblank(*s); s++);
return s;
}
static char *
columns(char *line, const struct keydef *kd)
{
char *rest;
char *start, *end;
unsigned i;
for(rest = line, i = 0; i < kd->start_column; i++) {
if(i != 0)
rest = next_blank(rest);
rest = next_nonblank(rest);
}
for(i = 1; i < kd->start_char && !isblank(*rest); i++, rest++);
start = rest;
if(kd->end_column) {
for(rest = line, i = 0; i < kd->end_column; i++) {
if(i != 0)
rest = next_blank(rest);
rest = next_nonblank(rest);
}
if(kd->end_char) {
for(i = 1; i < kd->end_char && *rest && !isblank(*rest); i++, rest++);
} else {
rest = next_blank(rest);
}
end = rest;
} else {
end = rest + strlen(rest);
}
return strndup(start, end - start);
}