Unverified Commit 348ff9e3 authored by David Disseldorp's avatar David Disseldorp Committed by Nathan Chancellor
Browse files

gen_init_cpio: avoid duplicate strlen calls 



We determine the filename length for the cpio header, so shouldn't
recalculate it when writing out the filename.

Signed-off-by: default avatarDavid Disseldorp <ddiss@suse.de>
Reviewed-by: default avatarNicolas Schier <nsc@kernel.org>
Link: https://lore.kernel.org/r/20250819032607.28727-5-ddiss@suse.de


Signed-off-by: default avatarNathan Chancellor <nathan@kernel.org>
parent 97169cd6

usr/gen_init_cpio.c

+24 −16
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#define str(s) xstr(s)

#define MIN(a, b) ((a) < (b) ? (a) : (b))

#define CPIO_HDR_LEN 110

#define CPIO_TRAILER "TRAILER!!!"

#define padlen(_off, _align) (((_align) - ((_off) & ((_align) - 1))) % (_align))



static char padding[512];
@@ -40,9 +41,8 @@ struct file_handler { 
	int (*handler)(const char *line);

};



static int push_string(const char *name)

static int push_buf(const char *name, size_t name_len)

{

	unsigned int name_len = strlen(name) + 1;

	ssize_t len;



	len = write(outfd, name, name_len);
@@ -69,9 +69,8 @@ static int push_pad(size_t padlen) 
	return 0;

}



static int push_rest(const char *name)

static int push_rest(const char *name, size_t name_len)

{

	unsigned int name_len = strlen(name) + 1;

	ssize_t len;



	len = write(outfd, name, name_len);
@@ -85,8 +84,8 @@ static int push_rest(const char *name) 


static int cpio_trailer(void)

{

	const char name[] = "TRAILER!!!";

	int len;

	unsigned int namesize = sizeof(CPIO_TRAILER);



	len = dprintf(outfd, "%s%08X%08X%08lX%08lX%08X%08lX"

	       "%08X%08X%08X%08X%08X%08X%08X",
@@ -102,12 +101,12 @@ static int cpio_trailer(void) 
		0,			/* minor */

		0,			/* rmajor */

		0,			/* rminor */

		(unsigned)strlen(name)+1, /* namesize */

		namesize,		/* namesize */

		0);			/* chksum */

	offset += len;



	if (len != CPIO_HDR_LEN ||

	    push_rest(name) < 0 ||

	    push_rest(CPIO_TRAILER, namesize) < 0 ||

	    push_pad(padlen(offset, 512)) < 0)

		return -1;
@@ -118,9 +117,12 @@ static int cpio_mkslink(const char *name, const char *target, 
			 unsigned int mode, uid_t uid, gid_t gid)

{

	int len;

	unsigned int namesize, targetsize = strlen(target) + 1;



	if (name[0] == '/')

		name++;

	namesize = strlen(name) + 1;



	len = dprintf(outfd, "%s%08X%08X%08lX%08lX%08X%08lX"

	       "%08X%08X%08X%08X%08X%08X%08X",

		do_csum ? "070702" : "070701", /* magic */
@@ -130,19 +132,19 @@ static int cpio_mkslink(const char *name, const char *target, 
		(long) gid,		/* gid */

		1,			/* nlink */

		(long) default_mtime,	/* mtime */

		(unsigned)strlen(target)+1, /* filesize */

		targetsize,		/* filesize */

		3,			/* major */

		1,			/* minor */

		0,			/* rmajor */

		0,			/* rminor */

		(unsigned)strlen(name) + 1,/* namesize */

		namesize,		/* namesize */

		0);			/* chksum */

	offset += len;



	if (len != CPIO_HDR_LEN ||

	    push_string(name) < 0 ||

	    push_buf(name, namesize) < 0 ||

	    push_pad(padlen(offset, 4)) < 0 ||

	    push_string(target) < 0 ||

	    push_buf(target, targetsize) < 0 ||

	    push_pad(padlen(offset, 4)) < 0)

		return -1;
@@ -172,9 +174,12 @@ static int cpio_mkgeneric(const char *name, unsigned int mode, 
		       uid_t uid, gid_t gid)

{

	int len;

	unsigned int namesize;



	if (name[0] == '/')

		name++;

	namesize = strlen(name) + 1;



	len = dprintf(outfd, "%s%08X%08X%08lX%08lX%08X%08lX"

	       "%08X%08X%08X%08X%08X%08X%08X",

		do_csum ? "070702" : "070701", /* magic */
@@ -189,12 +194,12 @@ static int cpio_mkgeneric(const char *name, unsigned int mode, 
		1,			/* minor */

		0,			/* rmajor */

		0,			/* rminor */

		(unsigned)strlen(name) + 1,/* namesize */

		namesize,		/* namesize */

		0);			/* chksum */

	offset += len;



	if (len != CPIO_HDR_LEN ||

	    push_rest(name) < 0)

	    push_rest(name, namesize) < 0)

		return -1;



	return 0;
@@ -265,6 +270,7 @@ static int cpio_mknod(const char *name, unsigned int mode, 
		       unsigned int maj, unsigned int min)

{

	int len;

	unsigned int namesize;



	if (dev_type == 'b')

		mode |= S_IFBLK;
@@ -273,6 +279,8 @@ static int cpio_mknod(const char *name, unsigned int mode, 


	if (name[0] == '/')

		name++;

	namesize = strlen(name) + 1;



	len = dprintf(outfd, "%s%08X%08X%08lX%08lX%08X%08lX"

	       "%08X%08X%08X%08X%08X%08X%08X",

		do_csum ? "070702" : "070701", /* magic */
@@ -287,12 +295,12 @@ static int cpio_mknod(const char *name, unsigned int mode, 
		1,			/* minor */

		maj,			/* rmajor */

		min,			/* rminor */

		(unsigned)strlen(name) + 1,/* namesize */

		namesize,		/* namesize */

		0);			/* chksum */

	offset += len;



	if (len != CPIO_HDR_LEN ||

	    push_rest(name) < 0)

	    push_rest(name, namesize) < 0)

		return -1;



	return 0;
@@ -426,7 +434,7 @@ static int cpio_mkfile(const char *name, const char *location, 
		offset += len;



		if (len != CPIO_HDR_LEN ||

		    push_string(name) < 0 ||

		    push_buf(name, namesize) < 0 ||

		    push_pad(padlen(offset, 4)) < 0)

			goto error;