libproc/common/Pidle.c

	Pidle.c revision 186f7fbf5e07d046b50e4e15c32b21f109b76c80
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <stdlib.h>
#include <libelf.h>
#include <libgen.h>
#include <string.h>
#include <strings.h>
#include <errno.h>
#include <sys/sysmacros.h>

#include "libproc.h"
#include "Pcontrol.h"

static ssize_t
Pread_idle(struct ps_prochandle *P, void *buf, size_t n, uintptr_t addr)
{
    size_t resid = n;

    while (resid > 0) {
        map_info_t *mp;
        uintptr_t mapoff;
        ssize_t len;
        off64_t off;

        if ((mp = Paddr2mptr(P, addr)) == NULL)
            break;

        mapoff = addr - mp->map_pmap.pr_vaddr;
        len = MIN(resid, mp->map_pmap.pr_size - mapoff);
        off = mp->map_offset + mapoff;

        if ((len = pread64(P->asfd, buf, len, off)) <= 0)
            break;

        resid -= len;
        addr += len;
        buf = (char *)buf + len;
    }

    return (n - resid);
}

/*ARGSUSED*/
static ssize_t
Pwrite_idle(struct ps_prochandle *P, const void *buf, size_t n, uintptr_t addr)
{
    errno = EIO;
    return (-1);
}

static const ps_rwops_t P_idle_ops = {
    Pread_idle,
    Pwrite_idle
};

static int
idle_add_mapping(struct ps_prochandle *P, GElf_Phdr *php, file_info_t *fp)
{
    prmap_t pmap;

    dprintf("mapping base %llx filesz %llu memsz %llu offset %llu\n",
        (u_longlong_t)php->p_vaddr, (u_longlong_t)php->p_filesz,
        (u_longlong_t)php->p_memsz, (u_longlong_t)php->p_offset);

    pmap.pr_vaddr = (uintptr_t)php->p_vaddr;
    pmap.pr_size = php->p_filesz;
    (void) strncpy(pmap.pr_mapname, fp->file_pname,
        sizeof (pmap.pr_mapname));
    pmap.pr_offset = php->p_offset;

    pmap.pr_mflags = 0;
    if (php->p_flags & PF_R)
        pmap.pr_mflags |= MA_READ;
    if (php->p_flags & PF_W)
        pmap.pr_mflags |= MA_WRITE;
    if (php->p_flags & PF_X)
        pmap.pr_mflags |= MA_EXEC;

    pmap.pr_pagesize = 0;
    pmap.pr_shmid = -1;

    return (Padd_mapping(P, php->p_offset, fp, &pmap));
}

struct ps_prochandle *
Pgrab_file(const char *fname, int *perr)
{
    struct ps_prochandle *P = NULL;
    char buf[PATH_MAX];
    GElf_Ehdr ehdr;
    Elf *elf = NULL;
    size_t phnum;
    file_info_t *fp = NULL;
    int fd;
    int i;

    if ((fd = open64(fname, O_RDONLY)) < 0) {
        dprintf("couldn't open file");
        *perr = (errno == ENOENT) ? G_NOEXEC : G_STRANGE;
        return (NULL);
    }

    if (elf_version(EV_CURRENT) == EV_NONE) {
        dprintf("libproc ELF version is more recent than libelf");
        *perr = G_ELF;
        goto err;
    }

    if ((P = calloc(1, sizeof (struct ps_prochandle))) == NULL) {
        *perr = G_STRANGE;
        goto err;
    }

    (void) mutex_init(&P->proc_lock, USYNC_THREAD, NULL);
    P->state = PS_IDLE;
    P->pid = (pid_t)-1;
    P->asfd = fd;
    P->ctlfd = -1;
    P->statfd = -1;
    P->agentctlfd = -1;
    P->agentstatfd = -1;
    P->info_valid = -1;
    P->ops = &P_idle_ops;
    Pinitsym(P);

    if ((elf = elf_begin(fd, ELF_C_READ, NULL)) == NULL) {
        *perr = G_ELF;
        return (NULL);
    }

    /*
     * Construct a file_info_t that corresponds to this file.
     */
    if ((fp = calloc(1, sizeof (file_info_t))) == NULL) {
        *perr = G_STRANGE;
        goto err;
    }

    if ((fp->file_lo = calloc(1, sizeof (rd_loadobj_t))) == NULL) {
        *perr = G_STRANGE;
        goto err;
    }

    if (*fname == '/') {
        (void) strncpy(fp->file_pname, fname, sizeof (fp->file_pname));
    } else {
        size_t sz;

        if (getcwd(fp->file_pname, sizeof (fp->file_pname) - 1) ==
            NULL) {
            *perr = G_STRANGE;
            goto err;
        }

        sz = strlen(fp->file_pname);
        (void) snprintf(&fp->file_pname[sz],
            sizeof (fp->file_pname) - sz, "/%s", fname);
    }

    fp->file_fd = fd;
    fp->file_lo->rl_lmident = LM_ID_BASE;
    if ((fp->file_lname = strdup(fp->file_pname)) == NULL) {
        *perr = G_STRANGE;
        goto err;
    }
    fp->file_lbase = basename(fp->file_lname);

    if ((P->execname = strdup(fp->file_pname)) == NULL) {
        *perr = G_STRANGE;
        goto err;
    }

    P->num_files++;
    list_link(fp, &P->file_head);

    if (gelf_getehdr(elf, &ehdr) == NULL) {
        *perr = G_STRANGE;
        goto err;
    }

    if (elf_getphnum(elf, &phnum) == 0) {
        *perr = G_STRANGE;
        goto err;
    }

    dprintf("Pgrab_file: program header count = %lu\n", (ulong_t)phnum);

    /*
     * Sift through the program headers making the relevant maps.
     */
    for (i = 0; i < phnum; i++) {
        GElf_Phdr phdr, *php;

        if ((php = gelf_getphdr(elf, i, &phdr)) == NULL) {
            *perr = G_STRANGE;
            goto err;
        }

        if (php->p_type != PT_LOAD)
            continue;

        if (idle_add_mapping(P, php, fp) != 0) {
            *perr = G_STRANGE;
            goto err;
        }
    }
    Psort_mappings(P);

    (void) elf_end(elf);

    P->map_exec = fp->file_map;

    P->status.pr_flags = PR_STOPPED;
    P->status.pr_nlwp = 0;
    P->status.pr_pid = (pid_t)-1;
    P->status.pr_ppid = (pid_t)-1;
    P->status.pr_pgid = (pid_t)-1;
    P->status.pr_sid = (pid_t)-1;
    P->status.pr_taskid = (taskid_t)-1;
    P->status.pr_projid = (projid_t)-1;
    P->status.pr_zoneid = (zoneid_t)-1;
    switch (ehdr.e_ident[EI_CLASS]) {
    case ELFCLASS32:
        P->status.pr_dmodel = PR_MODEL_ILP32;
        break;
    case ELFCLASS64:
        P->status.pr_dmodel = PR_MODEL_LP64;
        break;
    default:
        *perr = G_FORMAT;
        goto err;
    }

    /*
     * Pfindobj() checks what zone a process is associated with, so
     * we call it after initializing pr_zoneid to -1.  This ensures
     * we don't get associated with any zone on the system.
     */
    if (Pfindobj(P, fp->file_lname, buf, sizeof (buf)) != NULL) {
        free(P->execname);
        P->execname = strdup(buf);
        if ((fp->file_rname = strdup(buf)) != NULL)
            fp->file_rbase = basename(fp->file_rname);
    }

    /*
     * The file and map lists are complete, and will never need to be
     * adjusted.
     */
    P->info_valid = 1;

    return (P);
err:
    (void) close(fd);
    if (P != NULL)
        Pfree(P);
    if (elf != NULL)
        (void) elf_end(elf);
    return (NULL);
}