From: Baptiste Daroussin <bapt@FreeBSD.org>
Date: Thu, 5 Jan 2023 09:44:34 +0000 (+0100)
Subject: dumpfd2fd: use copy_file_range if available (add testsuite for it)
X-Git-Tag: RELEASE_1_4_0_a2~31
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cff8cfe2892448bed8fa2d741605c7c8a5e043e6;p=thirdparty%2Fmlmmj.git

dumpfd2fd: use copy_file_range if available (add testsuite for it)
---

diff --git a/ChangeLog b/ChangeLog
index bb82ad05..7b05bae8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,8 @@
 1.4.0-a2
  o Fix a crash with forged probe emails
  o mlmmj-send does not need anymore absolute path
+ o Use copy_file_range if available
+ o Use arc4random_uniform if available
 1.4.0-a1
  o Add a test suite
  o Modernize code (dprintf, posix_spawn, asprintf, getline, daemon, ...)
diff --git a/configure.ac b/configure.ac
index 5709f0e8..62164131 100644
--- a/configure.ac
+++ b/configure.ac
@@ -48,7 +48,7 @@ AM_CONDITIONAL(WANT_RECEIVESTRIP, test x"$enable_receive_strip" = xyes)
 AC_FUNC_MALLOC
 AC_CHECK_FUNCS([ftruncate memset socket strerror strncasecmp snprintf fcntl])
 AC_CHECK_FUNCS([nanosleep time strftime syslog regcomp regexec])
-AC_CHECK_FUNCS([arc4random_uniform])
+AC_CHECK_FUNCS([arc4random_uniform copy_file_range])
 PKG_CHECK_MODULES([ATF], [atf-c])
 
 AC_CONFIG_FILES([Makefile])
diff --git a/src/dumpfd2fd.c b/src/dumpfd2fd.c
index 009fcb1a..7e70eda4 100644
--- a/src/dumpfd2fd.c
+++ b/src/dumpfd2fd.c
@@ -1,6 +1,6 @@
-/* Copyright (C) 2004 Mads Martin Joergensen <mmj at mmj dot dk>
- *
- * $Id$
+/*
+ * Copyright (C) 2004 Mads Martin Joergensen <mmj at mmj dot dk>
+ * Copyright (C) 2023 Baptiste Daroussin <bapt@FreeBSD.org>
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to
@@ -21,31 +21,60 @@
  * IN THE SOFTWARE.
  */
 
+#include <sys/limits.h>
 #include <sys/types.h>
-#include <sys/stat.h>
 #include <fcntl.h>
 #include <unistd.h>
 #include <errno.h>
+#include <stdbool.h>
 
-#include "wrappers.h"
+#include "config.h"
 
 #define DUMPBUF 4096
 
-int dumpfd2fd(int infd, int outfd)
+static int
+_copy_file(int from, int to)
 {
-	size_t n;
 	char buf[DUMPBUF];
+	ssize_t r, wresid, w = 0;
+	char *bufp;
+	r = read(from, buf, DUMPBUF);
+	if (r < 0)
+		return (r);
+	for (bufp = buf, wresid = r; ; bufp += w, wresid -= w) {
+		w = write(to, bufp, wresid);
+		if (w <= 0)
+			break;
+		if (w >= (ssize_t) wresid)
+			break;
+	}
+	return (w < 0 ? w : r);
+}
+
+int dumpfd2fd(int from, int to)
+{
+#ifdef HAVE_COPY_FILE_RANGE2
+	bool cfr = true;
+#endif
+	int r;
 
-	while((n = read(infd, &buf, sizeof(buf))) != 0) {
-		if(n < 0) {
-			if(errno == EINTR)
-				continue;
-			else
-				return -1; /* Caller can check errno */
+	do {
+#ifdef HAVE_COPY_FILE_RANGE2
+		if (cfr) {
+			r = copy_file_range(from, NULL, to, NULL, SSIZE_MAX, 0);
+			if (r < 0 && errno == EINVAL) {
+				printf("la\n");
+				/* probably a non seekable FD */
+				cfr = false;
+			}
 		}
-		if(writen(outfd, &buf, n) < 0)
-			return -1; /* Caller can check errno */
-	}
-	
-	return 0;
+		if (!cfr) {
+#endif
+			r = _copy_file(from, to);
+#ifdef HAVE_COPY_FILE_RANGE2
+		}
+#endif
+	} while (r > 0);
+
+	return (r);
 }
diff --git a/tests/mlmmj.c b/tests/mlmmj.c
index cd6968ed..2a96a2c6 100644
--- a/tests/mlmmj.c
+++ b/tests/mlmmj.c
@@ -20,6 +20,7 @@
  * IN THE SOFTWARE.
  */
 
+#include <sys/fcntl.h>
 #include <sys/socket.h>
 #include <arpa/inet.h>
 #include <netinet/in.h>
@@ -107,6 +108,7 @@ ATF_TC_WITHOUT_HEAD(getlistaddr);
 ATF_TC_WITHOUT_HEAD(statctrl);
 ATF_TC_WITHOUT_HEAD(is_subbed_in);
 ATF_TC_WITHOUT_HEAD(getaddrsfromfile);
+ATF_TC_WITHOUT_HEAD(dumpfd2fd);
 
 #ifndef NELEM
 #define NELEM(array)    (sizeof(array) / sizeof((array)[0]))
@@ -1675,6 +1677,38 @@ ATF_TC_BODY(getaddrsfromfile, tc)
 	fclose(fp);
 }
 
+ATF_TC_BODY(dumpfd2fd, tc)
+{
+	FILE *plop = fopen("from", "w");
+	fprintf(plop, "bla\n");
+	fclose(plop);
+
+	int from = open("from", O_RDONLY);
+	int to = open("to.txt", O_WRONLY|O_CREAT|O_TRUNC, 0644);
+
+	ATF_REQUIRE_EQ_MSG(dumpfd2fd(from, to), 0, "Invalid simple copy");
+	close(from);
+	close(to);
+
+	if (!atf_utils_compare_file("to.txt", "bla\n")) {
+		atf_utils_cat_file("to.txt", "");
+		atf_tc_fail("Unexpected output");
+	}
+
+	/* non seekable */
+	int shm = shm_open("/tmp/myshm", O_RDWR | O_CREAT, 0644);
+	ftruncate(shm, strlen("bla\n"));
+	dprintf(shm, "bla\n");
+	from = shm_open("/tmp/myshm", O_RDONLY, 0644);
+	to = open("tobla.txt", O_WRONLY|O_CREAT|O_TRUNC, 0644);
+	int ret = dumpfd2fd(from, to);
+	ATF_REQUIRE_EQ_MSG(ret, 0, "Invalid simple copy %d", ret);
+	if (!atf_utils_compare_file("tobla.txt", "bla\n")) {
+		atf_utils_cat_file("tobla.txt", ">>");
+		atf_tc_fail("Unexpected output");
+	}
+}
+
 ATF_TP_ADD_TCS(tp)
 {
 	ATF_TP_ADD_TC(tp, random_int);
@@ -1728,6 +1762,7 @@ ATF_TP_ADD_TCS(tp)
 	ATF_TP_ADD_TC(tp, statctrl);
 	ATF_TP_ADD_TC(tp, is_subbed_in);
 	ATF_TP_ADD_TC(tp, getaddrsfromfile);
+	ATF_TP_ADD_TC(tp, dumpfd2fd);
 
 	return (atf_no_error());
 }