+/* vi: set sw=4 ts=4: */
/*
- * Mini find implementation for busybox
+ * Mini sort implementation for busybox
*
*
- * Copyright (C) 1999 by Lineo, inc.
+ * Copyright (C) 1999,2000 by Lineo, inc.
* Written by John Beppu <beppu@lineo.com>
*
* This program is free software; you can redistribute it and/or modify
#include <stdio.h>
#include <errno.h>
-static const char sort_usage[] =
-"Usage: sort [OPTION]... [FILE]...\n\n"
-;
+#ifdef BB_FEATURE_SORT_REVERSE
+#define APPLY_REVERSE(x) (reverse ? -(x) : (x))
+static int reverse = 0;
+#else
+#define APPLY_REVERSE(x) (x)
+#endif
+/* typedefs _______________________________________________________________ */
/* line node */
-typedef struct {
- char *data; /* line data */
- struct Line *next; /* pointer to next line node */
+typedef struct Line {
+ char *data; /* line data */
+ struct Line *next; /* pointer to next line node */
} Line;
/* singly-linked list of lines */
typedef struct {
- int len; /* number of Lines */
- Line *line; /* array fed to qsort */
- Line *head; /* head of List */
+ int len; /* number of Lines */
+ Line **sorted; /* array fed to qsort */
+ Line *head; /* head of List */
+ Line *current; /* current Line */
} List;
+/* comparison function */
+typedef int (Compare) (const void *, const void *);
+
-/* Line methods */
+/* methods ________________________________________________________________ */
static const int max = 1024;
-static Line *
-line_new()
+/* mallocate Line */
+static Line *line_alloc()
+{
+ Line *self;
+ self = malloc(1 * sizeof(Line));
+ return self;
+}
+
+/* Construct Line from FILE* */
+static Line *line_newFromFile(FILE * src)
+{
+ Line *self;
+ char *cstring = NULL;
+
+ if ((cstring = get_line_from_file(src))) {
+ self = line_alloc();
+ if (self == NULL) {
+ return NULL;
+ }
+ self->data = cstring;
+ self->next = NULL;
+ return self;
+ }
+ return NULL;
+}
+
+/* Line destructor */
+static Line *line_release(Line * self)
{
- char buffer[max];
+ if (self->data) {
+ free(self->data);
+ free(self);
+ }
+ return self;
}
/* Comparison */
-static int
-compare_ascii(const void *, const void *);
+/* ascii order */
+static int compare_ascii(const void *a, const void *b)
+{
+ Line **doh;
+ Line *x, *y;
-static int
-compare_numeric(const void *, const void *);
+ doh = (Line **) a;
+ x = *doh;
+ doh = (Line **) b;
+ y = *doh;
+ // fprintf(stdout, "> %p: %s< %p: %s", x, x->data, y, y->data);
+ return APPLY_REVERSE(strcmp(x->data, y->data));
+}
-/* List */
+/* numeric order */
+static int compare_numeric(const void *a, const void *b)
+{
+ Line **doh;
+ Line *x, *y;
+ int xint, yint;
-static void
-list_insert();
+ doh = (Line **) a;
+ x = *doh;
+ doh = (Line **) b;
+ y = *doh;
-static void
-list_sort();
+ xint = strtoul(x->data, NULL, 10);
+ yint = strtoul(y->data, NULL, 10);
-static void
-list_print();
+ return APPLY_REVERSE(xint - yint);
+}
+/* List */
-/*
- * I need a list
- * to insert lines into
- * then I need to sort this list
- * and finally print it
- */
+/* */
+static List *list_init(List * self)
+{
+ self->len = 0;
+ self->sorted = NULL;
+ self->head = NULL;
+ self->current = NULL;
+ return self;
+}
-int
-sort_main(int argc, char **argv)
+/* for simplicity, the List gains ownership of the line */
+static List *list_insert(List * self, Line * line)
{
- int i;
- char opt;
-
- /* default behaviour */
-
- /* parse argv[] */
- for (i = 1; i < argc; i++) {
- if (argv[i][0] == '-') {
- opt = argv[i][1];
- switch (opt) {
- case 'h':
- usage(sort_usage);
- break;
- default:
- fprintf(stderr, "sort: invalid option -- %c\n", opt);
- usage(sort_usage);
- }
+ if (line == NULL) {
+ return NULL;
+ }
+
+ /* first insertion */
+ if (self->head == NULL) {
+ self->head = line;
+ self->current = line;
+
+ /* all subsequent insertions */
} else {
- break;
+ self->current->next = line;
+ self->current = line;
+ }
+ self->len++;
+ return self;
+}
+
+/* order the list according to compare() */
+static List *list_sort(List * self, Compare * compare)
+{
+ int i;
+ Line *line;
+
+ /* mallocate array of Line*s */
+ self->sorted = (Line **) malloc(self->len * sizeof(Line *));
+ if (self->sorted == NULL) {
+ return NULL;
+ }
+
+ /* fill array w/ List's contents */
+ i = 0;
+ line = self->head;
+ while (line) {
+ self->sorted[i++] = line;
+ line = line->next;
+ }
+
+ /* apply qsort */
+ qsort(self->sorted, self->len, sizeof(Line *), compare);
+ return self;
+}
+
+/* precondition: list must be sorted */
+static List *list_writeToFile(List * self, FILE * dst)
+{
+ int i;
+ Line **line = self->sorted;
+
+ if (self->sorted == NULL) {
+ return NULL;
+ }
+ for (i = 0; i < self->len; i++) {
+ fprintf(dst, "%s", line[i]->data);
}
- }
+ return self;
+}
+
+/* deallocate */
+static void list_release(List * self)
+{
+ Line *i;
+ Line *die;
- /* go through remaining args (if any) */
- if (i >= argc) {
+ i = self->head;
+ while (i) {
+ die = i;
+ i = die->next;
+ line_release(die);
+ }
+}
+
+
+
+int sort_main(int argc, char **argv)
+{
+ int i;
+ char opt;
+ List list;
+ Line *l;
+ Compare *compare;
+
+ /* init */
+ compare = compare_ascii;
+ list_init(&list);
+
+ /* parse argv[] */
+ for (i = 1; i < argc; i++) {
+ if (argv[i][0] == '-') {
+ opt = argv[i][1];
+ switch (opt) {
+ case 'h':
+ usage(sort_usage);
+ break;
+ case 'n':
+ /* numeric comparison */
+ compare = compare_numeric;
+ break;
+#ifdef BB_FEATURE_SORT_REVERSE
+ case 'r':
+ /* reverse */
+ reverse = 1;
+ break;
+#endif
+ default:
+ errorMsg("invalid option -- %c\n", opt);
+ usage(sort_usage);
+ }
+ } else {
+ break;
+ }
+ }
+
+ /* this could be factored better */
+
+ /* work w/ stdin */
+ if (i >= argc) {
+ while ((l = line_newFromFile(stdin))) {
+ list_insert(&list, l);
+ }
+ list_sort(&list, compare);
+ list_writeToFile(&list, stdout);
+ list_release(&list);
+
+ /* work w/ what's left in argv[] */
+ } else {
+ FILE *src;
- } else {
- for ( ; i < argc; i++) {
+ for (; i < argc; i++) {
+ src = fopen(argv[i], "r");
+ if (src == NULL) {
+ break;
+ }
+ while ((l = line_newFromFile(src))) {
+ list_insert(&list, l);
+ }
+ fclose(src);
+ }
+ list_sort(&list, compare);
+ list_writeToFile(&list, stdout);
+ list_release(&list);
}
- }
- exit(0);
+ return(0);
}
-/* $Date: 1999/12/21 20:00:35 $ */
-/* $Id: sort.c,v 1.1 1999/12/21 20:00:35 beppu Exp $ */
+/* $Id: sort.c,v 1.20 2000/07/16 20:57:15 kraai Exp $ */
projects / oweals / busybox.git / blobdiff