add directory study

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

@@ -0,0 +1,100 @@
+/* chgrp  -  change group		 Author: Bert Reuling */
+
+/* This program is also chown.c */
+/*
+ * 89Dec07 Blayne Puklich Modified so that it checks its BASENAME
+ *		rather than the whole argv[0] to see who it should be.
+ *		Added slash(), which comes from dosread.c.
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <ctype.h>
+#include <pwd.h>
+#include <grp.h>
+#include <stdio.h>
+
+#ifndef TRUE
+#define TRUE  1
+#define FALSE 0
+#endif
+
+char *slash( /* char *str */ );
+
+main(argc, argv)
+int argc;
+char *argv[];
+{
+  int i, uid, gid, owner, status = 0;
+  struct passwd *pwd, *getpwuid(), *getpwnam();
+  struct group *grp, *getgrgid(), *getgrnam();
+  struct stat st;
+  char *name = slash(argv[0]);
+
+  if (strcmp(name, "chown") == 0)
+	owner = TRUE;
+  else if (strcmp(name, "chgrp") == 0)
+	owner = FALSE;
+  else {
+	fprintf(stderr, "%s: should be named \"chown\" or \"chgrp\"\n", name);
+	exit(1);
+  }
+
+  if (argc < 3) {
+	fprintf(stderr, 
+		 "Usage: %s %s file ...\n", name, (owner) ? "owner" : "group");
+	exit(1);
+  }
+  if (isdigit(argv[1][0])) {
+	if (owner)
+		pwd = getpwuid(atoi(argv[1]));
+	else
+		grp = getgrgid(atoi(argv[1]));
+  } else {
+	if (owner)
+		pwd = getpwnam(argv[1]);
+	else
+		grp = getgrnam(argv[1]);
+  }
+
+  if (owner && (pwd == (struct passwd *) 0)) {
+	fprintf(stderr, "%s: unknown user\n", name);
+	exit(1);
+  }
+  if (!owner && (grp == (struct group *) 0)) {
+	fprintf(stderr, "%s: unknown group\n", name);
+	exit(1);
+  }
+  for (i = 2; i < argc; i++) {
+	if (stat(argv[i], &st) != -1) {
+		if (owner) {
+			uid = pwd->pw_uid;	/* new owner */
+			gid = st.st_gid;	/* old group */
+		} else {
+			uid = st.st_uid;	/* old owner */
+			gid = grp->gr_gid;	/* new group */
+		}
+		if (chown(argv[i], uid, gid) == -1) {
+			fprintf(stderr, "%s: not changed\n", argv[i]);
+			status++;
+		}
+	} else {
+		perror(argv[i]);
+		status++;
+	}
+  }
+  exit(status);
+}
+
+/* Stolen from dosread.c 89Dec07 Blayne Puklich */
+
+char *slash(str)
+register char *str;
+{
+  register char *result = str;
+
+  while (*str)
+	if (*str++ == '/') result = str;
+
+  return result;
+}