random small size optimizations

libbb/messages.c

@@ -28,6 +28,7 @@ const char bb_msg_standard_input[] = "standard input";
 const char bb_msg_standard_output[] = "standard output";
 
 const char bb_str_default[] = "default";
+const char bb_hexdigits_upcase[] = "0123456789ABCDEF";
 
 const char bb_path_passwd_file[] = "/etc/passwd";
 const char bb_path_shadow_file[] = "/etc/shadow";

libbb/read.c

@@ -88,7 +88,7 @@ char *reads(int fd, char *buffer, size_t size)
 		*p++ = '\0';
 		// avoid incorrect (unsigned) widening
 		offset = (off_t)(p-buffer) - (off_t)size;
-		// set fd position the right after the \n
+		// set fd position right after '\n'
 		if (offset && lseek(fd, offset, SEEK_CUR) == (off_t)-1)
 			return NULL;
 	}

libbb/xfuncs.c

@@ -333,6 +333,19 @@ char *itoa(int n)
 	return local_buf;
 }
 
+// Emit a string of hex representation of bytes
+char *bin2hex(char *p, const char *cp, int count)
+{
+	while (count) {
+		unsigned char c = *cp++;
+		/* put lowercase hex digits */
+		*p++ = 0x10 | bb_hexdigits_upcase[c >> 4];
+		*p++ = 0x10 | bb_hexdigits_upcase[c & 0xf];
+		count--;
+	}
+	return p;
+}
+
 // Die with an error message if we can't set gid.  (Because resource limits may
 // limit this user to a given number of processes, and if that fills up the
 // setgid() will fail and we'll _still_be_root_, which is bad.)