From: Ian Darwin <ian@darwinsys.com>
Date: Tue, 8 Sep 1992 15:01:08 +0000 (+0000)
Subject: Hurray! Zoulos wrote in the missing glop to my framework, to actually
X-Git-Tag: FILE3_27~260
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6de84b3797473c68adcb4dc5676a486e5b9e52e2;p=file

Hurray! Zoulos wrote in the missing glop to my framework, to actually
*do* the uncompression of a .Z file.
---

diff --git a/src/compress.c b/src/compress.c
index eefebf50..300c58d5 100644
--- a/src/compress.c
+++ b/src/compress.c
@@ -3,6 +3,13 @@
  *	is_compress() returns 0 if uncompressed, number of bits if compressed.
  *	uncompress(old, n, newch) - uncompress old into new, return sizeof new
  */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/wait.h>
+
+#include "file.h"
 
 /* Check for compression, return nbits. Algorithm, in magic(4) format:
  * 0       string          \037\235        compressed data
@@ -11,7 +18,7 @@
  */
 int
 is_compress(p, b)
-unsigned char *p;
+const unsigned char *p;
 int *b;
 {
 
@@ -23,12 +30,56 @@ int *b;
 }
 
 int
-uncompress(old, n, newch)
-unsigned char *old, **newch;
+uncompress(old, newch, n)
+const unsigned char *old;
+unsigned char **newch;
 int n;
 {
-	*newch = old;	/* TODO write this */
-	**newch = 0;	/* prevent infinite loop, skeleton version only */
-	return n;
+	int fdin[2], fdout[2];
+
+	if (pipe(fdin) == -1 || pipe(fdout) == -1) {
+		error("cannot create pipe (%s).\n", strerror(errno));	
+		/*NOTREACHED*/
+	}
+	switch (fork()) {
+	case 0:	/* child */
+		(void) close(0);
+		(void) dup(fdin[0]);
+		(void) close(fdin[0]);
+		(void) close(fdin[1]);
+
+		(void) close(1);
+		(void) dup(fdout[1]);
+		(void) close(fdout[0]);
+		(void) close(fdout[1]);
+
+		execlp("uncompress", "uncompress", "-c", NULL);
+		error("could not execute `uncompress' (%s).\n", 
+		      strerror(errno));
+		/*NOTREACHED*/
+	case -1:
+		error("could not fork (%s).\n", strerror(errno));
+		/*NOTREACHED*/
+
+	default: /* parent */
+		(void) close(fdin[0]);
+		(void) close(fdout[1]);
+		if (write(fdin[1], old, n) != n) {
+			error("write failed (%s).\n", strerror(errno));
+			/*NOTREACHED*/
+		}
+		(void) close(fdin[1]);
+		if ((*newch = (unsigned char *) malloc(n)) == NULL) {
+			error("out of memory.\n");
+			/*NOTREACHED*/
+		}
+		if ((n = read(fdout[0], *newch, n)) <= 0) {
+			free(*newch);
+			error("read failed (%s).\n", strerror(errno));
+			/*NOTREACHED*/
+		}
+		(void) close(fdout[0]);
+		(void) wait(NULL);
+		return n;
+	}
 }
-