Exerc 5_02.

chapter_5.pointers_arrays/5_02.getfloat/Makefile

@@ -0,0 +1,5 @@
+BINARY=getfloat
+
+LFLAGS=-lm
+
+include ../../Makefile.exerc

chapter_5.pointers_arrays/5_02.getfloat/getch.c

@@ -0,0 +1,25 @@
+# include <stdio.h>
+
+# define BUFSIZE 128
+
+int buf[BUFSIZE];    /* buffer for ungetch */
+int bufp = 0;        /* next free position in buf */
+
+
+/* getch: get a (possibly pushed-back) character */
+int getch (void)
+{
+  return (bufp > 0) ? buf[--bufp] : getchar();
+}
+
+
+/* ungetch: push character back on input */
+void ungetch (int c)
+{
+  if (bufp >= BUFSIZE) {
+    printf("ungetch: too many characters\n");
+  } else {
+    buf[bufp++] = c;
+  }
+}
+

chapter_5.pointers_arrays/5_02.getfloat/getch.h

@@ -0,0 +1,9 @@
+# ifndef GETCH_H
+# define GETCH_H
+
+/* getch: get a (possibly pushed-back) character */
+int getch (void);
+/* ungetch: push character back on input */
+void ungetch (int c);
+
+# endif

chapter_5.pointers_arrays/5_02.getfloat/getfloat.c

@@ -0,0 +1,50 @@
+# include <stdio.h>
+# include <ctype.h>
+# include <math.h>
+# include "getch.h"
+
+/*
+  getfloat: get next floating-point number from input into *pn
+  return:
+   - 0 when it's not a number
+   - EOF when read ok and EOF reached
+   - positive integer when read ok
+*/
+int getfloat (float *pn)
+{
+  int c, sign;
+  unsigned int d;
+
+  while (isspace(c = getch())) /* skip white space */
+    ;
+  if (! isdigit(c) && c != EOF && c != '+' && c != '-') {
+    ungetch(c); /* it is not a number */
+    return 0;
+  }
+  sign = (c == '-') ? -1 : 1;
+  if (c == '+' || c == '-') {
+    if (! isdigit(c = getch()) && c != '.') {
+      ungetch(c);
+      ungetch(sign ? '+' : '-');
+      return 0;
+    }
+  }
+  *pn = 0;
+  while (isdigit(c)) {
+    *pn = 10 * *pn + (c - '0');
+    c = getch();
+  }
+  if (c == '.') {
+    d = 0;
+    while (isdigit(c = getch())) {
+      *pn = 10 * *pn + (c - '0');
+      d++;
+    }
+    *pn /= pow(10.0, d);
+  }
+  if (*pn != 0)
+    *pn *= sign;
+  if (c != EOF)
+    ungetch(c);
+  return c;
+}

chapter_5.pointers_arrays/5_02.getfloat/getfloat.h

@@ -0,0 +1,7 @@
+# ifndef GETFLOAT_H
+# define GETFLOAT_H
+
+/* getfloat: get next floating-point number from input into *pn */
+int getfloat (float *pn);
+
+# endif

chapter_5.pointers_arrays/5_02.getfloat/main.c

@@ -0,0 +1,19 @@
+# include <stdio.h>
+# include "getfloat.h"
+
+int main ()
+{
+  int r;
+  float n;
+
+  for (r = getfloat(&n); r != EOF && r != 0; r = getfloat(&n)) {
+    printf("float read: %f\n", n);
+  }
+  if (r == EOF) {
+    printf("(EOF)\n");
+  } else {
+    printf("not a number\n");
+  }
+
+  return 0;
+}

chapter_5.pointers_arrays/5_02.getfloat/tests/0_pos_ints.tin

@@ -0,0 +1 @@
+1 10 222

chapter_5.pointers_arrays/5_02.getfloat/tests/0_pos_ints.tout

@@ -0,0 +1,4 @@
+float read: 1.000000
+float read: 10.000000
+float read: 222.000000
+(EOF)

chapter_5.pointers_arrays/5_02.getfloat/tests/1_pos_neg_err.tin

@@ -0,0 +1 @@
+-1024 -0 +256 ++1000 

chapter_5.pointers_arrays/5_02.getfloat/tests/1_pos_neg_err.tout

@@ -0,0 +1,4 @@
+float read: -1024.000000
+float read: 0.000000
+float read: 256.000000
+not a number

chapter_5.pointers_arrays/5_02.getfloat/tests/2_pos_neg_whitespace.tin

@@ -0,0 +1,5 @@
+-100 -2
++5 -3		  0
+
+
+123456

chapter_5.pointers_arrays/5_02.getfloat/tests/2_pos_neg_whitespace.tout

@@ -0,0 +1,7 @@
+float read: -100.000000
+float read: -2.000000
+float read: 5.000000
+float read: -3.000000
+float read: 0.000000
+float read: 123456.000000
+(EOF)

chapter_5.pointers_arrays/5_02.getfloat/tests/3_pos_neg_floats.tin

@@ -0,0 +1 @@
+0.1 10.55 222.098694

chapter_5.pointers_arrays/5_02.getfloat/tests/3_pos_neg_floats.tout

@@ -0,0 +1,4 @@
+float read: 0.100000
+float read: 10.550000
+float read: 222.098694
+(EOF)

chapter_5.pointers_arrays/5_02.getfloat/tests/4_pos_neg_err_floats.tin

@@ -0,0 +1 @@
+ -.0501 +10. -123.33300 +.0 -. --

chapter_5.pointers_arrays/5_02.getfloat/tests/4_pos_neg_err_floats.tout

@@ -0,0 +1,6 @@
+float read: -0.050100
+float read: 10.000000
+float read: -123.333000
+float read: 0.000000
+float read: 0.000000
+not a number

chapter_5.pointers_arrays/5_02.getfloat/tests/5_pos_neg_floats_whitespace_err.tin

@@ -0,0 +1,6 @@
+	0.4      -100.000999
+
+   -.01
+ +3333
+
+-a.

chapter_5.pointers_arrays/5_02.getfloat/tests/5_pos_neg_floats_whitespace_err.tout

@@ -0,0 +1,5 @@
+float read: 0.400000
+float read: -100.000999
+float read: -0.010000
+float read: 3333.000000
+not a number