pcore.c

Sun Solaris 10 中的 DTrace 组件的源代码。请参看: http://www.sun.com/software/solaris/observability.jsp

		if ((P->auxv = malloc(sizeof (auxv_t) * (n + 1))) == NULL)
			return (-1);

		for (i = 0; i < n; i++)
			auxv_32_to_n(&a32[i], &P->auxv[i]);

	} else {
#endif
		n = nbytes / sizeof (auxv_t);
		nbytes = n * sizeof (auxv_t);

		if ((P->auxv = malloc(nbytes + sizeof (auxv_t))) == NULL)
			return (-1);

		if (read(P->asfd, P->auxv, nbytes) != nbytes) {
			free(P->auxv);
			P->auxv = NULL;
			return (-1);
		}
#ifdef _LP64
	}
#endif

	if (_libproc_debug) {
		for (i = 0; i < n; i++) {
			dprintf("P->auxv[%lu] = ( %d, 0x%lx )\n", (ulong_t)i,
			    P->auxv[i].a_type, P->auxv[i].a_un.a_val);
		}
	}

	/*
	 * Defensive coding for loops which depend upon the auxv array being
	 * terminated by an AT_NULL element; in each case, we've allocated
	 * P->auxv to have an additional element which we force to be AT_NULL.
	 */
	P->auxv[n].a_type = AT_NULL;
	P->auxv[n].a_un.a_val = 0L;
	P->nauxv = (int)n;

	return (0);
}

#ifdef __sparc
static int
note_xreg(struct ps_prochandle *P, size_t nbytes)
{
	lwp_info_t *lwp = P->core->core_lwp;
	size_t xbytes = sizeof (prxregset_t);
	prxregset_t *xregs;

	if (lwp == NULL || lwp->lwp_xregs != NULL || nbytes < xbytes)
		return (0);	/* No lwp yet, already seen, or bad size */

	if ((xregs = malloc(xbytes)) == NULL)
		return (-1);

	if (read(P->asfd, xregs, xbytes) != xbytes) {
		dprintf("Pgrab_core: failed to read NT_PRXREG\n");
		free(xregs);
		return (-1);
	}

	lwp->lwp_xregs = xregs;
	return (0);
}

static int
note_gwindows(struct ps_prochandle *P, size_t nbytes)
{
	lwp_info_t *lwp = P->core->core_lwp;

	if (lwp == NULL || lwp->lwp_gwins != NULL || nbytes == 0)
		return (0);	/* No lwp yet or already seen or no data */

	if ((lwp->lwp_gwins = malloc(sizeof (gwindows_t))) == NULL)
		return (-1);

	/*
	 * Since the amount of gwindows data varies with how many windows were
	 * actually saved, we just read up to the minimum of the note size
	 * and the size of the gwindows_t type.  It doesn't matter if the read
	 * fails since we have to zero out gwindows first anyway.
	 */
#ifdef _LP64
	if (P->core->core_dmodel == PR_MODEL_ILP32) {
		gwindows32_t g32;

		(void) memset(&g32, 0, sizeof (g32));
		(void) read(P->asfd, &g32, MIN(nbytes, sizeof (g32)));
		gwindows_32_to_n(&g32, lwp->lwp_gwins);

	} else {
#endif
		(void) memset(lwp->lwp_gwins, 0, sizeof (gwindows_t));
		(void) read(P->asfd, lwp->lwp_gwins,
		    MIN(nbytes, sizeof (gwindows_t)));
#ifdef _LP64
	}
#endif
	return (0);
}

#ifdef __sparcv9
static int
note_asrs(struct ps_prochandle *P, size_t nbytes)
{
	lwp_info_t *lwp = P->core->core_lwp;
	int64_t *asrs;

	if (lwp == NULL || lwp->lwp_asrs != NULL || nbytes < sizeof (asrset_t))
		return (0);	/* No lwp yet, already seen, or bad size */

	if ((asrs = malloc(sizeof (asrset_t))) == NULL)
		return (-1);

	if (read(P->asfd, asrs, sizeof (asrset_t)) != sizeof (asrset_t)) {
		dprintf("Pgrab_core: failed to read NT_ASRS\n");
		free(asrs);
		return (-1);
	}

	lwp->lwp_asrs = asrs;
	return (0);
}
#endif	/* __sparcv9 */
#endif	/* __sparc */

/*ARGSUSED*/
static int
note_notsup(struct ps_prochandle *P, size_t nbytes)
{
	dprintf("skipping unsupported note type\n");
	return (0);
}

/*
 * Populate a table of function pointers indexed by Note type with our
 * functions to process each type of core file note:
 */
static int (*nhdlrs[])(struct ps_prochandle *, size_t) = {
	note_notsup,		/*  0	unassigned		*/
	note_notsup,		/*  1	NT_PRSTATUS (old)	*/
	note_notsup,		/*  2	NT_PRFPREG (old)	*/
	note_notsup,		/*  3	NT_PRPSINFO (old)	*/
#ifdef __sparc
	note_xreg,		/*  4	NT_PRXREG		*/
#else
	note_notsup,		/*  4	NT_PRXREG		*/
#endif
	note_platform,		/*  5	NT_PLATFORM		*/
	note_auxv,		/*  6	NT_AUXV			*/
#ifdef __sparc
	note_gwindows,		/*  7	NT_GWINDOWS		*/
#ifdef __sparcv9
	note_asrs,		/*  8	NT_ASRS			*/
#else
	note_notsup,		/*  8	NT_ASRS			*/
#endif
#else
	note_notsup,		/*  7	NT_GWINDOWS		*/
	note_notsup,		/*  8	NT_ASRS			*/
#endif
#if defined(__i386) || defined(__amd64)
	note_ldt,		/*  9	NT_LDT			*/
#else
	note_notsup,		/*  9	NT_LDT			*/
#endif
	note_pstatus,		/* 10	NT_PSTATUS		*/
	note_notsup,		/* 11	unassigned		*/
	note_notsup,		/* 12	unassigned		*/
	note_psinfo,		/* 13	NT_PSINFO		*/
	note_cred,		/* 14	NT_PRCRED		*/
	note_utsname,		/* 15	NT_UTSNAME		*/
	note_lwpstatus,		/* 16	NT_LWPSTATUS		*/
	note_lwpsinfo,		/* 17	NT_LWPSINFO		*/
	note_priv,		/* 18	NT_PRPRIV		*/
	note_priv_info,		/* 19	NT_PRPRIVINFO		*/
	note_content,		/* 20	NT_CONTENT		*/
	note_zonename,		/* 21	NT_ZONENAME		*/
};

/*
 * Add information on the address space mapping described by the given
 * PT_LOAD program header.  We fill in more information on the mapping later.
 */
static int
core_add_mapping(struct ps_prochandle *P, GElf_Phdr *php)
{
	map_info_t *mp;
	int err = 0;

	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);


	mp = &P->mappings[P->map_count++];

	mp->map_offset = php->p_offset;
	mp->map_file = NULL;

	mp->map_pmap.pr_vaddr = (uintptr_t)php->p_vaddr;
	mp->map_pmap.pr_size = php->p_memsz;

	/*
	 * If Pgcore() or elfcore() fail to write a mapping, they will set
	 * PF_SUNW_FAILURE in the Phdr and try to stash away the errno for us.
	 */
	if (php->p_flags & PF_SUNW_FAILURE) {
		(void) pread64(P->asfd, &err,
		    sizeof (err), (off64_t)php->p_offset);

		Perror_printf(P, "core file data for mapping at %p not saved: "
		    "%s\n", (void *)(uintptr_t)php->p_vaddr, strerror(err));
		dprintf("core file data for mapping at %p not saved: %s\n",
		    (void *)(uintptr_t)php->p_vaddr, strerror(err));

	} else if (php->p_filesz != 0 && mp->map_offset >= P->core->core_size) {
		Perror_printf(P, "core file may be corrupt -- data for mapping "
		    "at %p is missing\n", (void *)(uintptr_t)php->p_vaddr);
		dprintf("core file may be corrupt -- data for mapping "
		    "at %p is missing\n", (void *)(uintptr_t)php->p_vaddr);
	}

	/*
	 * The mapping name and offset will hopefully be filled in
	 * by the librtld_db agent.  Unfortunately, if it isn't a
	 * shared library mapping, this information is gone forever.
	 */
	mp->map_pmap.pr_mapname[0] = '\0';
	mp->map_pmap.pr_offset = 0;

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

	if (php->p_filesz == 0)
		mp->map_pmap.pr_mflags |= MA_RESERVED1;

	/*
	 * At the time of adding this mapping, we just zero the pagesize.
	 * Once we've processed more of the core file, we'll have the
	 * pagesize from the auxv's AT_PAGESZ element and we can fill this in.
	 */
	mp->map_pmap.pr_pagesize = 0;

	/*
	 * Unfortunately whether or not the mapping was a System V
	 * shared memory segment is lost.  We use -1 to mark it as not shm.
	 */
	mp->map_pmap.pr_shmid = -1;
	return (0);
}

/*
 * Order mappings based on virtual address.  We use this function as the
 * callback for sorting the array of map_info_t pointers.
 */
static int
core_cmp_mapping(const void *lhsp, const void *rhsp)
{
	const map_info_t *lhs = lhsp;
	const map_info_t *rhs = rhsp;

	if (lhs->map_pmap.pr_vaddr == rhs->map_pmap.pr_vaddr)
		return (0);

	return (lhs->map_pmap.pr_vaddr < rhs->map_pmap.pr_vaddr ? -1 : 1);
}

/*
 * Given a virtual address, name the mapping at that address using the
 * specified name, and return the map_info_t pointer.
 */
static map_info_t *
core_name_mapping(struct ps_prochandle *P, uintptr_t addr, const char *name)
{
	map_info_t *mp = Paddr2mptr(P, addr);

	if (mp != NULL) {
		(void) strncpy(mp->map_pmap.pr_mapname, name, PRMAPSZ);
		mp->map_pmap.pr_mapname[PRMAPSZ - 1] = '\0';
	}

	return (mp);
}

/*
 * libproc uses libelf for all of its symbol table manipulation. This function
 * takes a symbol table and string table from a core file and places them
 * in a memory backed elf file.
 */
static void
fake_up_symtab(struct ps_prochandle *P, GElf_Ehdr *ehdr,
    GElf_Shdr *symtab, GElf_Shdr *strtab)
{
	size_t size;
	off64_t off, base;
	map_info_t *mp;
	file_info_t *fp;
	Elf_Scn *scn;
	Elf_Data *data;

	if (symtab->sh_addr == 0 ||
	    (mp = Paddr2mptr(P, symtab->sh_addr)) == NULL ||
	    (fp = mp->map_file) == NULL ||
	    fp->file_symtab.sym_data != NULL)
		return;

	if (P->status.pr_dmodel == PR_MODEL_ILP32) {
		struct {
			Elf32_Ehdr ehdr;
			Elf32_Shdr shdr[3];
			char data[1];
		} *b;

		base = sizeof (b->ehdr) + sizeof (b->shdr);
		size = base + symtab->sh_size + strtab->sh_size;

		if ((b = calloc(1, size)) == NULL)
			return;

		(void) memcpy(&b->ehdr, ehdr, offsetof(GElf_Ehdr, e_entry));
		b->ehdr.e_ehsize = sizeof (b->ehdr);
		b->ehdr.e_shoff = sizeof (b->ehdr);
		b->ehdr.e_shentsize = sizeof (b->shdr[0]);
		b->ehdr.e_shnum = 3;
		off = 0;

		b->shdr[1].sh_size = symtab->sh_size;
		b->shdr[1].sh_type = SHT_SYMTAB;
		b->shdr[1].sh_offset = off + base;
		b->shdr[1].sh_entsize = sizeof (Elf32_Sym);
		b->shdr[1].sh_link = 2;
		b->shdr[1].sh_info =  symtab->sh_info;
		b->shdr[1].sh_addralign = symtab->sh_addralign;

		if (pread64(P->asfd, &b->data[off], b->shdr[1].sh_size,
		    symtab->sh_offset) != b->shdr[1].sh_size) {
			free(b);
			return;
		}

		off += b->shdr[1].sh_size;

		b->shdr[2].sh_flags = SHF_STRINGS;
		b->shdr[2].sh_size = strtab->sh_size;
		b->shdr[2].sh_type = SHT_STRTAB;
		b->shdr[2].sh_offset = off + base;
		b->shdr[2].sh_info =  strtab->sh_info;
		b->shdr[2].sh_addralign = 1;

		if (pread64(P->asfd, &b->data[off], b->shdr[2].sh_size,
		    strtab->sh_offset) != b->shdr[2].sh_size) {
			free(b);
			return;
		}

		off += b->shdr[2].sh_size;

		fp->file_symtab.sym_elf = elf_memory((char *)b, size);
		if (fp->file_symtab.sym_elf == NULL) {
			free(b);
			return;
		}

		fp->file_symtab.sym_elfmem = b;
#ifdef _LP64
	} else {
		struct {
			Elf64_Ehdr ehdr;
			Elf64_Shdr shdr[3];
			char data[1];
		} *b;

		base = sizeof (b->ehdr) + sizeof (b->shdr);
		size = base + symtab->sh_size + strtab->sh_size;

		if ((b = calloc(1, size)) == NULL)
			return;

		(void) memcpy(&b->ehdr, ehdr, offsetof(GElf_Ehdr, e_entry));
		b->ehdr.e_ehsize = sizeof (b->ehdr);
		b->ehdr.e_shoff = sizeof (b->ehdr);
		b->ehdr.e_shentsize = sizeof (b->shdr[0]);
		b->ehdr.e_shnum = 3;
		off = 0;

		b->shdr[1].sh_size = symtab->sh_size;
		b->shdr[1].sh_type = SHT_SYMTAB;
		b->shdr[1].sh_offset = off + base;
		b->shdr[1].sh_entsize = sizeof (Elf64_Sym);
		b->shdr[1].sh_link = 2;
		b->shdr[1].sh_info =  symtab->sh_info;
		b->shdr[1].sh_addralign = symtab->sh_addralign;

		if (pread64(P->asfd, &b->data[off], b->shdr[1].sh_size,
		    symtab->sh_offset) != b->shdr[1].sh_size) {
			free(b);
			return;
		}

		off += b->shdr[1].sh_size;

		b->shdr[2].sh_flags = SHF_STRINGS;
		b->shdr[2].sh_size = strtab->sh_size;
		b->shdr[2].sh_type = SHT_STRTAB;
		b->shdr[2].sh_offset = off + base;
		b->shdr[2].sh_info =  strtab->sh_info;
		b->shdr[2].sh_addralign = 1;

		if (pread64(P->asfd, &b->data[off], b->shdr[2].sh_size,
		    strtab->sh_offset) != b->shdr[2].sh_size) {
			free(b);
			return;
		}

		off += b->shdr[2].sh_size;

		fp->file_symtab.sym_elf = elf_memory((char *)b, size);
		if (fp->file_symtab.sym_elf == NULL) {
			free(b);
			return;
		}

		fp->file_symtab.sym_elfmem = b;
#endif
	}

	if ((scn = elf_getscn(fp->file_symtab.sym_elf, 1)) == NULL ||
	    (fp->file_symtab.sym_data = elf_getdata(scn, NULL)) == NULL ||
	    (scn = elf_getscn(fp->file_symtab.sym_elf, 2)) == NULL ||
	    (data = elf_getdata(scn, NULL)) == NULL)
		goto err;

	fp->file_symtab.sym_strs = data->d_buf;
	fp->file_symtab.sym_strsz = data->d_size;
	fp->file_symtab.sym_symn = symtab->sh_size / symtab->sh_entsize;
	fp->file_symtab.sym_hdr = *symtab;
	fp->file_symtab.sym_strhdr = *strtab;

	optimize_symtab(&fp->file_symtab);

	return;
err:
	(void) elf_end(fp->file_symtab.sym_elf);
	free(fp->file_symtab.sym_elfmem);
	fp->file_symtab.sym_elf = NULL;
	fp->file_symtab.sym_elfmem = NULL;
}

static void
core_ehdr_to_gelf(const Elf32_Ehdr *src, GElf_Ehdr *dst)
{
	(void) memcpy(dst->e_ident, src->e_ident, EI_NIDENT);
	dst->e_type = src->e_type;
	dst->e_machine = src->e_machine;
	dst->e_version = src->e_version;
	dst->e_entry = (Elf64_Addr)src->e_entry;
	dst->e_phoff = (Elf64_Off)src->e_phoff;
	dst->e_shoff = (Elf64_Off)src->e_shoff;
	dst->e_flags = src->e_flags;
	dst->e_ehsize = src->e_ehsize;
	dst->e_phentsize = src->e_phentsize;
	dst->e_phnum = src->e_phnum;
	dst->e_shentsize = src->e_shentsize;
	dst->e_shnum = src->e_shnum;
	dst->e_shstrndx = src->e_shstrndx;
}

static void
core_phdr_to_gelf(const Elf32_Phdr *src, GElf_Phdr *dst)
{
	dst->p_type = src->p_type;
	dst->p_flags = src->p_flags;
	dst->p_offset = (Elf64_Off)src->p_offset;
	dst->p_vaddr = (Elf64_Addr)src->p_vaddr;
	dst->p_paddr = (Elf64_Addr)src->p_paddr;
	dst->p_filesz = (Elf64_Xword)src->p_filesz;
	dst->p_memsz = (Elf64_Xword)src->p_memsz;
	dst->p_align = (Elf64_Xword)src->p_align;
}

static void
core_shdr_to_gelf(const Elf32_Shdr *src, GElf_Shdr *dst)
{
	dst->sh_name = src->sh_name;
	dst->sh_type = src->sh_type;
	dst->sh_flags = (Elf64_Xword)src->sh_flags;
	dst->sh_addr = (Elf64_Addr)src->sh_addr;
	dst->sh_offset = (Elf64_Off)src->sh_offset;
	dst->sh_size = (Elf64_Xword)src->sh_size;
	dst->sh_link = src->sh_link;
	dst->sh_info = src->sh_info;
	dst->sh_addralign = (Elf64_Xword)src->sh_addralign;
	dst->sh_entsize = (Elf64_Xword)src->sh_entsize;
}

/*
 * Perform elf_begin on efp->e_fd and verify the ELF file's type and class.
 */
static int
core_elf_fdopen(elf_file_t *efp, GElf_Half type, int *perr)