implemented numeric sort (sort -g)

[oweals/busybox.git] / coreutils / sort.c

diff --git a/coreutils/sort.c b/coreutils/sort.c
index f3f9fca1d671a9b249a6c97b4f1b8165edfc85c7..127d683198039470a1623aeff360a8924d8b5476 100644 (file)
--- a/coreutils/sort.c
+++ b/coreutils/sort.c
@@ -1,5 +1,5 @@
 /*
- * Mini find implementation for busybox
+ * Mini sort implementation for busybox
  *
  *
  * Copyright (C) 1999 by Lineo, inc.
@@ -32,23 +32,26 @@ static const char sort_usage[] =
 "Usage: sort [OPTION]... [FILE]...\n\n"
 ;
 
-/* structs ________________________________________________________________ */
+/* 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       *sorted;    /* array fed to qsort */
+    int         len;        /* number of Lines */
+    Line        **sorted;   /* array fed to qsort */
 
-    Line       *head;      /* head of List */
-    Line       *current    /* current Line */
+    Line        *head;      /* head of List */
+    Line        *current;   /* current Line */
 } List;
 
+/* comparison function */
+typedef int (Compare)(const void *, const void *);
+
 
 /* methods ________________________________________________________________ */
 
@@ -104,11 +107,40 @@ line_release(Line *self)
 
 /* Comparison */
 
+/* ascii order */
 static int
-compare_ascii(const void *, const void *);
+compare_ascii(const void *a, const void *b)
+{
+    Line **doh;
+    Line *x, *y;
 
+    doh = (Line **) a;
+    x   = *doh;
+    doh = (Line **) b;
+    y   = *doh;
+
+    // fprintf(stdout, "> %p: %s< %p: %s", x, x->data, y, y->data);
+    return strcmp(x->data, y->data);
+}
+
+/* numeric order */
 static int
-compare_numeric(const void *, const void *);
+compare_numeric(const void *a, const void *b)
+{
+    Line    **doh;
+    Line    *x, *y;
+    int            xint, yint;
+
+    doh  = (Line **) a;
+    x    = *doh;
+    doh  = (Line **) b;
+    y    = *doh;
+
+    xint = strtoul(x->data, NULL, 10);
+    yint = strtoul(y->data, NULL, 10);
+
+    return (xint - yint);
+}
 
 
 /* List */
@@ -125,7 +157,7 @@ list_init(List *self)
 }
 
 /* for simplicity, the List gains ownership of the line */
-static void
+static List *
 list_insert(List *self, Line *line)
 {
     if (line == NULL) { return NULL; }
@@ -137,26 +169,53 @@ list_insert(List *self, Line *line)
 
     /* all subsequent insertions */
     } else {
-       self->current->next = line;
+       self->current->next = line; 
        self->current       = line;
     }
     self->len++;
     return self;
 }
 
-/* */
+/* order the list according to compare() */
 static List *
-list_sort(List *self);
+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 List *
+static void
 list_release(List *self)
 {
     Line *i;
@@ -166,9 +225,8 @@ list_release(List *self)
     while (i) {
        die = i;
        i = die->next;
-       line_delete(die);
+       line_release(die);
     }
-    return self; /* bad poetry? */
 }
 
 
@@ -182,16 +240,24 @@ list_release(List *self)
 int 
 sort_main(int argc, char **argv)
 {
-    int i;
-    char opt;
+    int            i;
+    char    opt;
+    List    list;
+    Line    *l;
+    Compare *compare;
 
-    /* default behaviour */
+    /* 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 'g':
+                   compare = compare_numeric;
+                   break;
                case 'h':
                    usage(sort_usage);
                    break;
@@ -206,7 +272,12 @@ sort_main(int argc, char **argv)
 
     /* go through remaining args (if any) */
     if (i >= argc) {
-
+       while ( (l = line_newFromFile(stdin))) {
+           list_insert(&list, l);
+       }
+       list_sort(&list, compare);
+       list_writeToFile(&list, stdout);
+       list_release(&list);
     } else {
        for ( ; i < argc; i++) {
        }
@@ -215,4 +286,24 @@ sort_main(int argc, char **argv)
     exit(0);
 }
 
-/* $Id: sort.c,v 1.3 1999/12/22 17:57:31 beppu Exp $ */
+/* $Id: sort.c,v 1.7 1999/12/23 00:02:49 beppu Exp $ */
+/* 
+ * $Log: sort.c,v $
+ * Revision 1.7  1999/12/23 00:02:49  beppu
+ *     implemented numeric sort (sort -g)
+ *
+ * Revision 1.6  1999/12/22 23:02:12  beppu
+ *     oops..  qsort(2) misunderstanding on my part.
+ *     it's ok, now.
+ *
+ * Revision 1.5  1999/12/22 22:27:01  beppu
+ * playing w/ $Log: sort.c,v $
+ * playing w/ Revision 1.7  1999/12/23 00:02:49  beppu
+ * playing w/  implemented numeric sort (sort -g)
+ * playing w/
+ * playing w/ Revision 1.6  1999/12/22 23:02:12  beppu
+ * playing w/  oops..  qsort(2) misunderstanding on my part.
+ * playing w/  it's ok, now.
+ * playing w/
+ *
+ */