Commit b6a3e690 authored by Richard Henderson's avatar Richard Henderson
Browse files

osdep: Create qemu_getauxval and qemu_init_auxval 



Abstract away dependence on a system implementation of getauxval.

Signed-off-by: default avatarRichard Henderson <rth@twiddle.net>
parent 7dc65c02

include/qemu/osdep.h

+25 −0
Original line number Diff line number Diff line
@@ -215,4 +215,29 @@ bool fips_get_state(void); 
 */

char *qemu_get_local_state_pathname(const char *relative_pathname);



/**

 * qemu_getauxval:

 * @type: the auxiliary vector key to lookup

 *

 * Search the auxiliary vector for @type, returning the value

 * or 0 if @type is not present.

 */

#if defined(CONFIG_GETAUXVAL) || defined(__linux__)

unsigned long qemu_getauxval(unsigned long type);

#else

static inline unsigned long qemu_getauxval(unsigned long type) { return 0; }

#endif



/**

 * qemu_init_auxval:

 * @envp: the third argument to main

 *

 * If supported and required, locate the auxiliary vector at program startup.

 */

#if defined(CONFIG_GETAUXVAL) || !defined(__linux__)

static inline void qemu_init_auxval(char **envp) { }

#else

void qemu_init_auxval(char **envp);

#endif



#endif

linux-user/main.c

+1 −0
Original line number Diff line number Diff line
@@ -3701,6 +3701,7 @@ int main(int argc, char **argv, char **envp) 


    module_call_init(MODULE_INIT_QOM);



    qemu_init_auxval(envp);

    qemu_cache_utils_init(envp);



    if ((envlist = envlist_create()) == NULL) {

util/Makefile.objs

+1 −0
Original line number Diff line number Diff line
@@ -12,3 +12,4 @@ util-obj-y += qemu-option.o qemu-progress.o 
util-obj-y += hexdump.o

util-obj-y += crc32c.o

util-obj-y += throttle.o

util-obj-y += getauxval.o

util/getauxval.c

0 → 100644
+74 −0
Original line number Diff line number Diff line 
/*

 * QEMU access to the auxiliary vector

 *

 * Copyright (C) 2013 Red Hat, Inc

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */



#include "qemu-common.h"

#include "qemu/osdep.h"



#ifdef CONFIG_GETAUXVAL

/* Don't inline this in qemu/osdep.h, because pulling in <sys/auxv.h> for

   the system declaration of getauxval pulls in the system <elf.h>, which

   conflicts with qemu's version.  */



#include <sys/auxv.h>



unsigned long qemu_getauxval(unsigned long key)

{

    return getauxval(key);

}

#elif defined(__linux__)

#include "elf.h"



/* Our elf.h doesn't contain Elf32_auxv_t and Elf64_auxv_t, which is ok because

   that just makes it easier to define it properly for the host here.  */

typedef struct {

    unsigned long a_type;

    unsigned long a_val;

} ElfW_auxv_t;



static const ElfW_auxv_t *auxv;



void qemu_init_auxval(char **envp)

{

    /* The auxiliary vector is located just beyond the initial environment.  */

    while (*envp++ != NULL) {

        continue;

    }

    auxv = (const ElfW_auxv_t *)envp;

}



unsigned long qemu_getauxval(unsigned long type)

{

    /* If we were able to find the auxiliary vector, use it.  */

    if (auxv) {

        const ElfW_auxv_t *a;

        for (a = auxv; a->a_type != 0; a++) {

            if (a->a_type == type) {

                return a->a_val;

            }

        }

    }



    return 0;

}

#endif

vl.c

+1 −0
Original line number Diff line number Diff line
@@ -2894,6 +2894,7 @@ int main(int argc, char **argv, char **envp) 
    init_clocks();

    rtc_clock = QEMU_CLOCK_HOST;



    qemu_init_auxval(envp);

    qemu_cache_utils_init(envp);



    QLIST_INIT (&vm_change_state_head);