From 80bdcb77bd985a9e3bbefef0841a23e5dc43db11 Mon Sep 17 00:00:00 2001 From: John Gilmore Date: Thu, 11 Jun 1992 08:10:04 +0000 Subject: * elf.c (elf_obj_tdata): Merge elf_obj_tdata_struct and elf_core_tdata_struct into a single common struct. Core files wouldn't have worked at all without this. (bfd_elf_find_section): New function for GDB's undercover use to find string sections that BFD hides from it. (elf_get_str_section): Avoid multiple alloc&reads for same data; lint. (elf_object_p, elf_core_file_p): Allocate internal file header storage dynamically. * bfd.c (union {...} tdata): Remove elf_core_tdata_struct. * demo64.c: Prevent "empty translation unit" warnings from idiots. --- bfd/elf.c | 331 ++++++++++++++++++++++++++++++++++---------------------------- 1 file changed, 183 insertions(+), 148 deletions(-) (limited to 'bfd/elf.c') diff --git a/bfd/elf.c b/bfd/elf.c index 9841b00..fe4d37c 100644 --- a/bfd/elf.c +++ b/bfd/elf.c @@ -103,32 +103,25 @@ typedef struct } elf_symbol_type; /* Some private data is stashed away for future use using the tdata pointer - in the bfd structure. This information is different for ELF core files - and other ELF files. */ + in the bfd structure. */ -typedef struct elf_core_tdata_struct +struct elf_obj_tdata { - void *prstatus; /* The raw /proc prstatus structure */ - void *prpsinfo; /* The raw /proc prpsinfo structure */ -} elf_core_tdata; - -#define core_prpsinfo(bfd) (((bfd)->tdata.elf_core_data) -> prpsinfo) -#define core_prstatus(bfd) (((bfd)->tdata.elf_core_data) -> prstatus) - - -typedef struct elf_obj_tdata_struct -{ - Elf_Internal_Ehdr *elf_header; + Elf_Internal_Ehdr elf_header[1]; /* Actual data, but ref like ptr */ Elf_Internal_Shdr *elf_sect_ptr; struct strtab *strtab_ptr; int symtab_section; -} elf_obj_tdata; + void *prstatus; /* The raw /proc prstatus structure */ + void *prpsinfo; /* The raw /proc prpsinfo structure */ +}; #define elf_tdata(bfd) ((bfd) -> tdata.elf_obj_data) #define elf_elfheader(bfd) (elf_tdata(bfd) -> elf_header) #define elf_elfsections(bfd) (elf_tdata(bfd) -> elf_sect_ptr) #define elf_shstrtab(bfd) (elf_tdata(bfd) -> strtab_ptr) #define elf_onesymtab(bfd) (elf_tdata(bfd) -> symtab_section) +#define core_prpsinfo(bfd) (elf_tdata(bfd) -> prpsinfo) +#define core_prstatus(bfd) (elf_tdata(bfd) -> prstatus) /* Translate an ELF symbol in external format into an ELF symbol in internal format. */ @@ -332,7 +325,27 @@ static struct sec * EXFUN(section_from_elf_index, (bfd *, int)); static int EXFUN(elf_section_from_bfd_section, (bfd *, struct sec *)); static boolean EXFUN(elf_slurp_symbol_table, (bfd *, Elf_Internal_Shdr*)); static void EXFUN(elf_info_to_howto, (bfd *, arelent *, Elf_Internal_Rela *)); +static char *EXFUN(elf_get_str_section, (bfd *, unsigned int)); +/* Helper functions for GDB to locate the string tables. */ + +Elf_Internal_Shdr * +DEFUN(bfd_elf_find_section, (abfd, name), /* .stabstr offset */ + bfd *abfd AND + char *name) +{ + Elf_Internal_Shdr *i_shdrp = elf_elfsections (abfd); + char *shstrtab = elf_get_str_section (abfd, elf_elfheader (abfd)->e_shstrndx); + unsigned int max = elf_elfheader (abfd)->e_shnum; + unsigned int i; + + for (i = 1; i < max; i++) + if (!strcmp (&shstrtab[i_shdrp[i].sh_name], name)) + return &i_shdrp[i]; + return 0; +} + +/* End of GDB support. */ static char * DEFUN(elf_get_str_section, (abfd, shindex), @@ -342,14 +355,19 @@ DEFUN(elf_get_str_section, (abfd, shindex), Elf_Internal_Shdr *i_shdrp = elf_elfsections (abfd); unsigned int shstrtabsize = i_shdrp[shindex].sh_size; unsigned int offset = i_shdrp[shindex].sh_offset; - char *shstrtab; + char *shstrtab = i_shdrp[shindex].rawdata; + + if (shstrtab) + return shstrtab; + if ((shstrtab = elf_read (abfd, offset, shstrtabsize)) == NULL) { return (NULL); } i_shdrp[shindex].rawdata = (void*)shstrtab; - + return shstrtab; } + static char * DEFUN(elf_string_from_elf_section, (abfd, shindex, strindex), bfd *abfd AND @@ -358,6 +376,7 @@ DEFUN(elf_string_from_elf_section, (abfd, shindex, strindex), { Elf_Internal_Shdr *i_shdrp = elf_elfsections (abfd); Elf_Internal_Shdr *hdr = i_shdrp + shindex; + if (! hdr->rawdata) { if (elf_get_str_section (abfd, shindex) == NULL) @@ -462,8 +481,10 @@ DEFUN(bfd_section_from_shdr, (abfd, shindex), target_sect->flags |= SEC_RELOC; target_sect->relocation = 0; target_sect->rel_filepos = hdr->sh_offset; +#if 0 fprintf(stderr, "ELF>> section %s reading %d relocs\n", target_sect->name, target_sect->reloc_count); +#endif return true; } @@ -471,16 +492,23 @@ DEFUN(bfd_section_from_shdr, (abfd, shindex), case SHT_HASH: case SHT_DYNAMIC: case SHT_DYNSYM: /* could treat this like symtab... */ +#if 0 fprintf(stderr, "Dynamic Linking sections not yet supported.\n"); abort (); +#endif break; case SHT_NOTE: +#if 0 fprintf(stderr, "Note Sections not yet supported.\n"); abort (); +#endif break; case SHT_SHLIB: +#if 0 fprintf(stderr, "SHLIB Sections not supported (and non conforming.)\n"); +#endif return true; + default: break; } @@ -1001,7 +1029,7 @@ static bfd_target * DEFUN (elf_object_p, (abfd), bfd *abfd) { Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ - Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */ + Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */ Elf_External_Shdr x_shdr; /* Section header table entry, external form */ Elf_Internal_Shdr *i_shdrp; /* Section header table, internal form */ int shindex; @@ -1065,27 +1093,27 @@ wrong: /* Allocate an instance of the elf_obj_tdata structure and hook it up to the tdata pointer in the bfd. */ - if ((abfd -> tdata.elf_obj_data = - (elf_obj_tdata*) bfd_zalloc (abfd, sizeof (elf_obj_tdata))) - == NULL) + if (NULL == (elf_tdata (abfd) = (struct elf_obj_tdata *) + bfd_zalloc (abfd, sizeof (struct elf_obj_tdata)))) { bfd_error = no_memory; return (NULL); } + /* FIXME: Any `wrong' exits below here will leak memory (tdata). */ + /* Now that we know the byte order, swap in the rest of the header */ - elf_swap_ehdr_in (abfd, &x_ehdr, &i_ehdr); - /* FIXME: should be alloc'ed */ - elf_elfheader (abfd) = &i_ehdr; + i_ehdrp = elf_elfheader (abfd); + elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp); /* If there is no section header table, we're hosed. */ - if (i_ehdr.e_shoff == 0) + if (i_ehdrp->e_shoff == 0) goto wrong; - if (i_ehdr.e_type == ET_EXEC || i_ehdr.e_type == ET_DYN) + if (i_ehdrp->e_type == ET_EXEC || i_ehdrp->e_type == ET_DYN) abfd -> flags |= EXEC_P; - switch (i_ehdr.e_machine) + switch (i_ehdrp->e_machine) { case EM_NONE: case EM_M32: /* or should this be bfd_arch_obscure? */ @@ -1119,21 +1147,21 @@ wrong: check, verify that the what BFD thinks is the size of each section header table entry actually matches the size recorded in the file. */ - if (i_ehdr.e_shentsize != sizeof (x_shdr)) + if (i_ehdrp->e_shentsize != sizeof (x_shdr)) goto wrong; i_shdrp = (Elf_Internal_Shdr *) - bfd_alloc (abfd, sizeof (*i_shdrp) * i_ehdr.e_shnum); + bfd_alloc (abfd, sizeof (*i_shdrp) * i_ehdrp->e_shnum); if (! i_shdrp) { bfd_error = no_memory; return (NULL); } - if (bfd_seek (abfd, i_ehdr.e_shoff, SEEK_SET) == -1) + if (bfd_seek (abfd, i_ehdrp->e_shoff, SEEK_SET) == -1) { bfd_error = system_call_error; return (NULL); } - for (shindex = 0; shindex < i_ehdr.e_shnum; shindex++) + for (shindex = 0; shindex < i_ehdrp->e_shnum; shindex++) { if (bfd_read ((PTR) &x_shdr, sizeof x_shdr, 1, abfd) != sizeof (x_shdr)) @@ -1152,7 +1180,7 @@ wrong: bfd_section_from_shdr with it (since this particular strtab is used to find all of the ELF section names.) */ - shstrtab = elf_get_str_section (abfd, i_ehdr.e_shstrndx); + shstrtab = elf_get_str_section (abfd, i_ehdrp->e_shstrndx); if (! shstrtab) return (NULL); @@ -1164,14 +1192,14 @@ wrong: offset and section size for both the symbol table section and the associated string table section. */ - for (shindex = 1; shindex < i_ehdr.e_shnum; shindex++) + for (shindex = 1; shindex < i_ehdrp->e_shnum; shindex++) { bfd_section_from_shdr (abfd, shindex); } /* Remember the entry point specified in the ELF file header. */ - bfd_get_start_address (abfd) = i_ehdr.e_entry; + bfd_get_start_address (abfd) = i_ehdrp->e_entry; return (abfd->xvec); } @@ -1193,7 +1221,7 @@ static bfd_target * DEFUN (elf_core_file_p, (abfd), bfd *abfd) { Elf_External_Ehdr x_ehdr; /* Elf file header, external form */ - Elf_Internal_Ehdr i_ehdr; /* Elf file header, internal form */ + Elf_Internal_Ehdr *i_ehdrp; /* Elf file header, internal form */ Elf_External_Phdr x_phdr; /* Program header table entry, external form */ Elf_Internal_Phdr *i_phdrp; /* Program header table, internal form */ unsigned int phindex; @@ -1250,46 +1278,49 @@ wrong: goto wrong; } - /* Now that we know the byte order, swap in the rest of the header */ - elf_swap_ehdr_in (abfd, &x_ehdr, &i_ehdr); - - /* If there is no program header, or the type is not a core file, then - we are hosed. */ - if (i_ehdr.e_phoff == 0 || i_ehdr.e_type != ET_CORE) - goto wrong; - - /* Allocate an instance of the elf_core_tdata structure and hook it up to + /* Allocate an instance of the elf_obj_tdata structure and hook it up to the tdata pointer in the bfd. */ - abfd->tdata.elf_core_data = - (elf_core_tdata *) bfd_zalloc (abfd, sizeof (elf_core_tdata)); - if (abfd->tdata.elf_core_data == NULL) + elf_tdata (abfd) = + (struct elf_obj_tdata *) bfd_zalloc (abfd, sizeof (struct elf_obj_tdata)); + if (elf_tdata (abfd) == NULL) { bfd_error = no_memory; return (NULL); } + /* FIXME, `wrong' returns from this point onward, leak memory. */ + + /* Now that we know the byte order, swap in the rest of the header */ + i_ehdrp = elf_elfheader (abfd); + elf_swap_ehdr_in (abfd, &x_ehdr, i_ehdrp); + + /* If there is no program header, or the type is not a core file, then + we are hosed. */ + if (i_ehdrp->e_phoff == 0 || i_ehdrp->e_type != ET_CORE) + goto wrong; + /* Allocate space for a copy of the program header table in - internal form, seek to the program header table in the file, + internal form, seek to the program header table in the file, read it in, and convert it to internal form. As a simple sanity check, verify that the what BFD thinks is the size of each program header table entry actually matches the size recorded in the file. */ - if (i_ehdr.e_phentsize != sizeof (x_phdr)) + if (i_ehdrp->e_phentsize != sizeof (x_phdr)) goto wrong; i_phdrp = (Elf_Internal_Phdr *) - bfd_alloc (abfd, sizeof (*i_phdrp) * i_ehdr.e_phnum); + bfd_alloc (abfd, sizeof (*i_phdrp) * i_ehdrp->e_phnum); if (! i_phdrp) { bfd_error = no_memory; return (NULL); } - if (bfd_seek (abfd, i_ehdr.e_phoff, SEEK_SET) == -1) + if (bfd_seek (abfd, i_ehdrp->e_phoff, SEEK_SET) == -1) { bfd_error = system_call_error; return (NULL); } - for (phindex = 0; phindex < i_ehdr.e_phnum; phindex++) + for (phindex = 0; phindex < i_ehdrp->e_phnum; phindex++) { if (bfd_read ((PTR) &x_phdr, sizeof (x_phdr), 1, abfd) != sizeof (x_phdr)) @@ -1303,7 +1334,7 @@ wrong: /* Once all of the program headers have been read and converted, we can start processing them. */ - for (phindex = 0; phindex < i_ehdr.e_phnum; phindex++) + for (phindex = 0; phindex < i_ehdrp->e_phnum; phindex++) { bfd_section_from_phdr (abfd, i_phdrp + phindex, phindex); if ((i_phdrp + phindex) -> p_type == PT_NOTE) @@ -1314,7 +1345,7 @@ wrong: /* Remember the entry point specified in the ELF file header. */ - bfd_get_start_address (abfd) = i_ehdr.e_entry; + bfd_get_start_address (abfd) = i_ehdrp->e_entry; return (abfd->xvec); } @@ -1324,8 +1355,8 @@ DEFUN (elf_mkobject, (abfd), bfd *abfd) { /* this just does initialization */ /* coff_mkobject zalloc's space for tdata.coff_obj_data ... */ - elf_tdata(abfd) = (elf_obj_tdata *) - bfd_zalloc (abfd, sizeof(elf_obj_tdata)); + elf_tdata(abfd) = (struct elf_obj_tdata *) + bfd_zalloc (abfd, sizeof(struct elf_obj_tdata)); if (elf_tdata(abfd) == 0) { bfd_error = no_memory; return false; @@ -1526,103 +1557,101 @@ DEFUN (elf_compute_section_file_positions, (abfd), bfd *abfd) elf_sect_thunk est; if (! elf_shstrtab (abfd)) { - i_ehdrp = (Elf_Internal_Ehdr *) - bfd_alloc (abfd, sizeof (*i_ehdrp)); - shstrtab = bfd_new_strtab(abfd); - - i_ehdrp->e_ident[EI_MAG0] = ELFMAG0; - i_ehdrp->e_ident[EI_MAG1] = ELFMAG1; - i_ehdrp->e_ident[EI_MAG2] = ELFMAG2; - i_ehdrp->e_ident[EI_MAG3] = ELFMAG3; - - i_ehdrp->e_ident[EI_CLASS] = ELFCLASS32; /* FIXME: find out from bfd */ - i_ehdrp->e_ident[EI_DATA] = - abfd->xvec->byteorder_big_p ? ELFDATA2MSB : ELFDATA2LSB; - i_ehdrp->e_ident[EI_VERSION] = EV_CURRENT; - - for(count = EI_PAD; count < EI_NIDENT; count ++) - i_ehdrp->e_ident[count] = 0; + i_ehdrp = elf_elfheader (abfd); /* build new header in tdata memory */ + shstrtab = bfd_new_strtab(abfd); - i_ehdrp->e_type = (abfd->flags & EXEC_P)? ET_EXEC : ET_REL; - switch(bfd_get_arch(abfd)) - { - case bfd_arch_unknown: - i_ehdrp->e_machine = EM_NONE; - break; - case bfd_arch_sparc: - i_ehdrp->e_machine = EM_SPARC; - break; - case bfd_arch_i386: - i_ehdrp->e_machine = EM_386; - break; - case bfd_arch_m68k: - i_ehdrp->e_machine = EM_68K; - break; - case bfd_arch_m88k: - i_ehdrp->e_machine = EM_88K; - break; - case bfd_arch_i860: - i_ehdrp->e_machine = EM_860; - break; - case bfd_arch_mips: /* MIPS Rxxxx */ - i_ehdrp->e_machine = EM_MIPS; /* only MIPS R3000 */ - break; - /* also note that EM_M32, AT&T WE32100 is unknown to bfd */ - default: - i_ehdrp->e_machine = EM_NONE; - } - i_ehdrp->e_version = EV_CURRENT; - i_ehdrp->e_ehsize = sizeof(Elf_External_Ehdr); - - /* no program header, for now. */ - i_ehdrp->e_phoff = 0; - i_ehdrp->e_phentsize = 0; - i_ehdrp->e_phnum = 0; + i_ehdrp->e_ident[EI_MAG0] = ELFMAG0; + i_ehdrp->e_ident[EI_MAG1] = ELFMAG1; + i_ehdrp->e_ident[EI_MAG2] = ELFMAG2; + i_ehdrp->e_ident[EI_MAG3] = ELFMAG3; + + i_ehdrp->e_ident[EI_CLASS] = ELFCLASS32; /* FIXME: find out from bfd */ + i_ehdrp->e_ident[EI_DATA] = + abfd->xvec->byteorder_big_p ? ELFDATA2MSB : ELFDATA2LSB; + i_ehdrp->e_ident[EI_VERSION] = EV_CURRENT; + + for(count = EI_PAD; count < EI_NIDENT; count ++) + i_ehdrp->e_ident[count] = 0; + + i_ehdrp->e_type = (abfd->flags & EXEC_P)? ET_EXEC : ET_REL; + switch(bfd_get_arch(abfd)) + { + case bfd_arch_unknown: + i_ehdrp->e_machine = EM_NONE; + break; + case bfd_arch_sparc: + i_ehdrp->e_machine = EM_SPARC; + break; + case bfd_arch_i386: + i_ehdrp->e_machine = EM_386; + break; + case bfd_arch_m68k: + i_ehdrp->e_machine = EM_68K; + break; + case bfd_arch_m88k: + i_ehdrp->e_machine = EM_88K; + break; + case bfd_arch_i860: + i_ehdrp->e_machine = EM_860; + break; + case bfd_arch_mips: /* MIPS Rxxxx */ + i_ehdrp->e_machine = EM_MIPS; /* only MIPS R3000 */ + break; + /* also note that EM_M32, AT&T WE32100 is unknown to bfd */ + default: + i_ehdrp->e_machine = EM_NONE; + } + i_ehdrp->e_version = EV_CURRENT; + i_ehdrp->e_ehsize = sizeof(Elf_External_Ehdr); + + /* no program header, for now. */ + i_ehdrp->e_phoff = 0; + i_ehdrp->e_phentsize = 0; + i_ehdrp->e_phnum = 0; - /* each bfd section is section header entry */ - i_ehdrp->e_entry = bfd_get_start_address (abfd); - i_ehdrp->e_shentsize = sizeof (Elf_External_Shdr); + /* each bfd section is section header entry */ + i_ehdrp->e_entry = bfd_get_start_address (abfd); + i_ehdrp->e_shentsize = sizeof (Elf_External_Shdr); - /* can't do this: we'll need many more... */ - /* i_ehdr.e_shnum = bfd_count_sections(abfd)+1; /* include 0th, shstrtab */ - /* figure at most each section can have a rel, strtab, symtab */ - maxsections = 4*bfd_count_sections(abfd)+2; + /* can't do this: we'll need many more... */ + /* i_ehdr.e_shnum = bfd_count_sections(abfd)+1; /* include 0th, shstrtab */ + /* figure at most each section can have a rel, strtab, symtab */ + maxsections = 4*bfd_count_sections(abfd)+2; - i_ehdrp->e_shoff = i_ehdrp->e_ehsize; + i_ehdrp->e_shoff = i_ehdrp->e_ehsize; - /* and we'll just have to fix up the offsets later. */ - /* outbase += i_ehdr.e_shentsize * i_ehdr.e_shnum; */ - - i_shdrp = (Elf_Internal_Shdr *) - bfd_alloc (abfd, sizeof (*i_shdrp) * maxsections); - if (! i_shdrp) - { - bfd_error = no_memory; - return (false); - } - for (count=0; count < maxsections; count++) - { - i_shdrp[count].rawdata = 0; - i_shdrp[count].contents = 0; - } - - - i_shdrp[0].sh_name = 0; - i_shdrp[0].sh_type = SHT_NULL; - i_shdrp[0].sh_flags = 0; - i_shdrp[0].sh_addr = 0; - i_shdrp[0].sh_offset = 0; - i_shdrp[0].sh_size = 0; - i_shdrp[0].sh_link = SHN_UNDEF; - i_shdrp[0].sh_info = 0; - i_shdrp[0].sh_addralign = 0; - i_shdrp[0].sh_entsize = 0; - - i_ehdrp->e_shnum = 1; - - elf_elfheader (abfd) = i_ehdrp; - elf_elfsections (abfd) = i_shdrp; - elf_shstrtab (abfd) = shstrtab; + /* and we'll just have to fix up the offsets later. */ + /* outbase += i_ehdr.e_shentsize * i_ehdr.e_shnum; */ + + i_shdrp = (Elf_Internal_Shdr *) + bfd_alloc (abfd, sizeof (*i_shdrp) * maxsections); + if (! i_shdrp) + { + bfd_error = no_memory; + return (false); + } + for (count=0; count < maxsections; count++) + { + i_shdrp[count].rawdata = 0; + i_shdrp[count].contents = 0; + } + + + i_shdrp[0].sh_name = 0; + i_shdrp[0].sh_type = SHT_NULL; + i_shdrp[0].sh_flags = 0; + i_shdrp[0].sh_addr = 0; + i_shdrp[0].sh_offset = 0; + i_shdrp[0].sh_size = 0; + i_shdrp[0].sh_link = SHN_UNDEF; + i_shdrp[0].sh_info = 0; + i_shdrp[0].sh_addralign = 0; + i_shdrp[0].sh_entsize = 0; + + i_ehdrp->e_shnum = 1; + + elf_elfsections (abfd) = i_shdrp; + elf_shstrtab (abfd) = shstrtab; } est.i_ehdr = elf_elfheader(abfd); est.i_shdrp = elf_elfsections(abfd); @@ -1921,6 +1950,12 @@ DEFUN (elf_slurp_symbol_table, (abfd, hdr), sym -> name = elf_string_from_elf_section(abfd, hdr->sh_link, i_sym.st_name); sym -> value = i_sym.st_value; +/* FIXME -- this is almost certainly bogus. It's from Pace Willisson's + hasty Solaris support, to pass the sizes of object files or functions + down into GDB via the back door, to circumvent some other kludge in + how Sun hacked stabs. */ + sym -> udata = (PTR)i_sym.st_size; +/* FIXME -- end of bogosity. */ if (i_sym.st_shndx > 0 && i_sym.st_shndx < SHN_LORESERV) { sym -> section = section_from_elf_index (abfd, i_sym.st_shndx); -- cgit v1.1