add directory study

study/linux-travel/MINIX-1.5/1.5/Source/commands/prep.c

@@ -0,0 +1,124 @@
+/* prep - prepare file for statistics 	Author: Andy Tanenbaum */
+
+#include <ctype.h>
+#include <stdio.h>
+
+#define TROFF_CHAR	'.'	/* troff commands begin with this char */
+#define EOL		'\n'	/* end of line char */
+#define APOSTROPHE	047	/* single quote */
+#define BACKSLASH       '\\'	/* troff code */
+
+int lfread;			/* set when last char read was lf */
+int lfwritten;			/* set when last char written was lf */
+
+main(argc, argv)
+int argc;
+char *argv[];
+{
+
+  int c, backslash();
+  FILE *freopen();
+
+  if (argc > 2) usage();
+  if (argc == 2) {
+	if (freopen(argv[1], "r", stdin) == NULL) {
+		printf("prep: cannot open %s\n", argv[1]);
+		exit(1);
+	}
+  }
+  while ((c = getchar()) != EOF) {
+	/* Lines beginning with "." are troff commands -- skip them. */
+	if (lfread && c == TROFF_CHAR) {
+		skipline();
+		continue;
+	}
+	if (c == BACKSLASH) c = backslash();	/* eat troff stuff */
+
+	if (isupper(c)) {
+		putchar(tolower(c));
+		lfwritten = 0;
+		lfread = 0;
+		continue;
+	}
+	if (islower(c)) {
+		putchar(c);
+		lfwritten = 0;
+		lfread = 0;
+		continue;
+	}
+	if (c == APOSTROPHE) {
+		putchar(c);
+		lfwritten = 0;
+		lfread = 0;
+		continue;
+	}
+	lfread = (c == EOL ? 1 : 0);
+	if (lfwritten) continue;
+	putchar(EOL);
+	lfwritten = 1;
+  }
+  exit(0);
+}
+
+
+skipline()
+{
+  char c;
+
+  while ((c = getchar()) != EOL);
+}
+
+
+int backslash()
+{
+/* A backslash has been seen.  Eat troff stuff. */
+
+  int c;
+
+  c = getchar();
+  switch (c) {
+      case 'f':
+	c = getchar();
+	c = getchar();
+	return(c);
+
+      case 's':			/* \s7  or \s14 */
+	c = getchar();
+	c = getchar();
+	if (isdigit(c)) c = getchar();
+	return(c);
+
+      case 'n':			/* \na or \n(xx  */
+	c = getchar();
+	if (c == '(') {
+		c = getchar();
+		c = getchar();
+	}
+	c = getchar();
+	return(c);
+
+      case '*':			/* / * (XX */
+	c = getchar();
+	if (c == '(') {
+		c = getchar();
+		c = getchar();
+		c = getchar();
+		return(c);
+	}
+      case '(':			/* troff 4-character escape sequence */
+	c = getchar();
+	c = getchar();
+	c = getchar();
+	return(c);
+
+      default:
+	return(c);
+
+  }
+}
+
+usage()
+{
+  printf("Usage: prep [file]\n");
+  exit(1);
+}