0e4690d4e

Rob Landley

2006-08-20

SOURCE BUG Duration: 26s

Subject

Michael Opdenacker contributed a readahead applet.

SOURCE BUG

This commit was genuinely broken at the time (not related to our build system): scripts/config/mkconfigs.c (2005-08-01 - 2006-10-05 arasi) uretilen bbconfigopts.h icine .config satirlarini kacissiz, ham newline'larla gömüyordu - gecerli C degildi, busybox'un kendi bb_mkdep araci bile parse edemiyordu (7d219aab7 ile duzeltildi, mkconfigs shell scripte cevrildi)

→ Bu hatanin tam hikayesini ve duzeltme diffini gor

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

include/applets.h +1 -0 include/usage.h +6 -0 miscutils/Config.in +16 -0 miscutils/Makefile.in +1 -0 miscutils/readahead.c +36 -0

include/applets.h+1 -0

@@ -219,6 +219,7 @@ USE_PRINTF(APPLET(printf, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
	USE_PS(APPLET(ps, _BB_DIR_BIN, _BB_SUID_NEVER))
	USE_PWD(APPLET(pwd, _BB_DIR_BIN, _BB_SUID_NEVER))
	USE_RDATE(APPLET(rdate, _BB_DIR_USR_SBIN, _BB_SUID_NEVER))
+	USE_READAHEAD(APPLET(readahead, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
	USE_READLINK(APPLET(readlink, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
	USE_READPROFILE(APPLET(readprofile, _BB_DIR_USR_SBIN, _BB_SUID_NEVER))
	USE_REALPATH(APPLET(realpath, _BB_DIR_USR_BIN, _BB_SUID_NEVER))

include/usage.h+6 -0

@@ -2385,6 +2385,12 @@ USE_FEATURE_MDEV_CONFIG( \
	"\t-s\tSet the system date and time (default)\n" \
	"\t-p\tPrint the date and time"

+	#define readahead_trivial_usage \
+	"[FILE]..."
+	#define readahead_full_usage \
+	"Preloads FILE(s) in RAM cache so that subsequent reads for those" \
+	"files do not block on disk I/O."
+
	#ifdef CONFIG_FEATURE_READLINK_FOLLOW
	#define USAGE_READLINK_FOLLOW(a) a
	#else

miscutils/Config.in+16 -0

@@ -276,6 +276,22 @@ config CONFIG_MT
	to advance or rewind a tape past a specified number of archive
	files on the tape.

+	config CONFIG_READAHEAD
+	bool "readahead"
+	default n
+	help
+	Preload the files listed on the command line into RAM cache so that
+	subsequent reads on these files will not block on disk I/O.
+
+	This applet just calls the readahead(2) system call on each file.
+	It is mainly useful in system startup scripts to preload files
+	or executables before they are used. When used at the right time
+	(in particular when a CPU boundprocess is running) it can
+	significantly speed up system startup.
+
+	As readahead(2) blocks until each file has been read, it is best to
+	run this applet as a background job.
+
	config CONFIG_RUNLEVEL
	bool "runlevel"
	default n

miscutils/Makefile.in+1 -0

@@ -24,6 +24,7 @@ MISCUTILS-${CONFIG_LESS} += less.o
	MISCUTILS-$(CONFIG_MAKEDEVS) += makedevs.o
	MISCUTILS-$(CONFIG_MOUNTPOINT) += mountpoint.o
	MISCUTILS-$(CONFIG_MT) += mt.o
+	MISCUTILS-$(CONFIG_READAHEAD) += readahead.o
	MISCUTILS-$(CONFIG_RUNLEVEL) += runlevel.o
	MISCUTILS-$(CONFIG_RX) += rx.o
	MISCUTILS-$(CONFIG_SETSID) += setsid.o

miscutils/readahead.c+36 -0

@@ -0,0 +1,36 @@
+	/* vi: set sw=4 ts=4: */
+	/*
+	* readahead implementation for busybox
+	*
+	* Preloads the given files in RAM, to reduce access time.
+	* Does this by calling the readahead(2) system call.
+	*
+	* Copyright (C) 2006 Michael Opdenacker <[email protected]>
+	*
+	* Licensed under GPLv2 or later, see file License in this tarball for details.
+	*/
+
+	#include "busybox.h"
+
+	int readahead_main(int argc, char **argv)
+	{
+	FILE *f;
+	struct stat stat_buf;
+	int retval = EXIT_SUCCESS;
+
+	if (argc == 1) bb_show_usage();
+
+	while (*++argv) {
+	if ((f = bb_wfopen(*argv, "r")) != NULL) {
+	int r, fd=fileno(f);
+
+	xstat(*argv, &stat_buf);
+	r = readahead(fd, 0, fdlength(fd));
+	fclose(f);
+	if (r >= 0) continue;
+	}
+	retval = EXIT_FAILURE;
+	}
+
+	return retval;
+	}