Date: Tue, 4 Jun 2019 18:34:05 +0000 (UTC) From: Mark Johnston <markj@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r348657 - head/contrib/elftoolchain/elfcopy Message-ID: <201906041834.x54IY5Qs035508@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: markj Date: Tue Jun 4 18:34:05 2019 New Revision: 348657 URL: https://svnweb.freebsd.org/changeset/base/348657 Log: elfcopy: Use libelftc's string table routines to build .shstrtab. This replaces some hand-rolled routines and is substantially faster since libelftc uses a hash table for lookups and insertions, whereas elfcopy would perform a linear scan of the table. PR: 234949 Reviewed by: emaste MFC after: 2 weeks Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D20473 Modified: head/contrib/elftoolchain/elfcopy/ascii.c head/contrib/elftoolchain/elfcopy/binary.c head/contrib/elftoolchain/elfcopy/elfcopy.h head/contrib/elftoolchain/elfcopy/main.c head/contrib/elftoolchain/elfcopy/sections.c Modified: head/contrib/elftoolchain/elfcopy/ascii.c ============================================================================== --- head/contrib/elftoolchain/elfcopy/ascii.c Tue Jun 4 18:31:52 2019 (r348656) +++ head/contrib/elftoolchain/elfcopy/ascii.c Tue Jun 4 18:34:05 2019 (r348657) @@ -378,9 +378,6 @@ done: errx(EXIT_FAILURE, "gelf_update_ehdr() failed: %s", elf_errmsg(-1)); - /* Generate section name string table (.shstrtab). */ - set_shstrtab(ecp); - /* Update sh_name pointer for each section header entry. */ update_shdr(ecp, 0); @@ -604,9 +601,6 @@ done: if (gelf_update_ehdr(ecp->eout, &oeh) == 0) errx(EXIT_FAILURE, "gelf_update_ehdr() failed: %s", elf_errmsg(-1)); - - /* Generate section name string table (.shstrtab). */ - set_shstrtab(ecp); /* Update sh_name pointer for each section header entry. */ update_shdr(ecp, 0); Modified: head/contrib/elftoolchain/elfcopy/binary.c ============================================================================== --- head/contrib/elftoolchain/elfcopy/binary.c Tue Jun 4 18:31:52 2019 (r348656) +++ head/contrib/elftoolchain/elfcopy/binary.c Tue Jun 4 18:34:05 2019 (r348657) @@ -250,11 +250,8 @@ create_elf_from_binary(struct elfcopy *ecp, int ifd, c errx(EXIT_FAILURE, "gelf_update_ehdr() failed: %s", elf_errmsg(-1)); - /* Generate section name string table (.shstrtab). */ - ecp->flags |= SYMTAB_EXIST; - set_shstrtab(ecp); - /* Update sh_name pointer for each section header entry. */ + ecp->flags |= SYMTAB_EXIST; update_shdr(ecp, 0); /* Properly set sh_link field of .symtab section. */ Modified: head/contrib/elftoolchain/elfcopy/elfcopy.h ============================================================================== --- head/contrib/elftoolchain/elfcopy/elfcopy.h Tue Jun 4 18:31:52 2019 (r348656) +++ head/contrib/elftoolchain/elfcopy/elfcopy.h Tue Jun 4 18:34:05 2019 (r348657) @@ -135,6 +135,8 @@ struct section { int pseudo; int nocopy; + Elftc_String_Table *strtab; + TAILQ_ENTRY(section) sec_list; /* next section */ }; @@ -313,7 +315,6 @@ struct sec_action *lookup_sec_act(struct elfcopy *_ecp struct symop *lookup_symop_list(struct elfcopy *_ecp, const char *_name, unsigned int _op); void resync_sections(struct elfcopy *_ecp); -void set_shstrtab(struct elfcopy *_ecp); void setup_phdr(struct elfcopy *_ecp); void update_shdr(struct elfcopy *_ecp, int _update_link); Modified: head/contrib/elftoolchain/elfcopy/main.c ============================================================================== --- head/contrib/elftoolchain/elfcopy/main.c Tue Jun 4 18:31:52 2019 (r348656) +++ head/contrib/elftoolchain/elfcopy/main.c Tue Jun 4 18:34:05 2019 (r348657) @@ -388,9 +388,6 @@ create_elf(struct elfcopy *ecp) */ copy_content(ecp); - /* Generate section name string table (.shstrtab). */ - set_shstrtab(ecp); - /* * Second processing of output sections: Update section headers. * At this stage we set name string index, update st_link and st_info @@ -485,6 +482,9 @@ free_elf(struct elfcopy *ecp) /* Free symbol table buffers. */ free_symtab(ecp); + + /* Free section name string table. */ + elftc_string_table_destroy(ecp->shstrtab->strtab); /* Free internal section list. */ if (!TAILQ_EMPTY(&ecp->v_sec)) { Modified: head/contrib/elftoolchain/elfcopy/sections.c ============================================================================== --- head/contrib/elftoolchain/elfcopy/sections.c Tue Jun 4 18:31:52 2019 (r348656) +++ head/contrib/elftoolchain/elfcopy/sections.c Tue Jun 4 18:34:05 2019 (r348657) @@ -42,19 +42,18 @@ static void check_section_rename(struct elfcopy *ecp, static void filter_reloc(struct elfcopy *ecp, struct section *s); static int get_section_flags(struct elfcopy *ecp, const char *name); static void insert_sections(struct elfcopy *ecp); -static void insert_to_strtab(struct section *t, const char *s); static int is_append_section(struct elfcopy *ecp, const char *name); static int is_compress_section(struct elfcopy *ecp, const char *name); static int is_debug_section(const char *name); static int is_dwo_section(const char *name); static int is_modify_section(struct elfcopy *ecp, const char *name); static int is_print_section(struct elfcopy *ecp, const char *name); -static int lookup_string(struct section *t, const char *s); static void modify_section(struct elfcopy *ecp, struct section *s); static void pad_section(struct elfcopy *ecp, struct section *s); static void print_data(const char *d, size_t sz); static void print_section(struct section *s); static void *read_section(struct section *s, size_t *size); +static void set_shstrtab(struct elfcopy *ecp); static void update_reloc(struct elfcopy *ecp, struct section *s); static void update_section_group(struct elfcopy *ecp, struct section *s); @@ -1336,10 +1335,9 @@ insert_sections(struct elfcopy *ecp) void add_to_shstrtab(struct elfcopy *ecp, const char *name) { - struct section *s; - s = ecp->shstrtab; - insert_to_strtab(s, name); + if (elftc_string_table_insert(ecp->shstrtab->strtab, name) == 0) + errx(EXIT_FAILURE, "elftc_string_table_insert failed"); } void @@ -1349,6 +1347,9 @@ update_shdr(struct elfcopy *ecp, int update_link) GElf_Shdr osh; int elferr; + /* Finalize the section name string table (.shstrtab). */ + set_shstrtab(ecp); + TAILQ_FOREACH(s, &ecp->v_sec, sec_list) { if (s->pseudo) continue; @@ -1358,7 +1359,8 @@ update_shdr(struct elfcopy *ecp, int update_link) elf_errmsg(-1)); /* Find section name in string table and set sh_name. */ - osh.sh_name = lookup_string(ecp->shstrtab, s->name); + osh.sh_name = elftc_string_table_lookup(ecp->shstrtab->strtab, + s->name); /* * sh_link needs to be updated, since the index of the @@ -1408,19 +1410,22 @@ init_shstrtab(struct elfcopy *ecp) s->loadable = 0; s->type = SHT_STRTAB; s->vma = 0; + s->strtab = elftc_string_table_create(0); - insert_to_strtab(s, ""); - insert_to_strtab(s, ".symtab"); - insert_to_strtab(s, ".strtab"); - insert_to_strtab(s, ".shstrtab"); + add_to_shstrtab(ecp, ""); + add_to_shstrtab(ecp, ".symtab"); + add_to_shstrtab(ecp, ".strtab"); + add_to_shstrtab(ecp, ".shstrtab"); } -void +static void set_shstrtab(struct elfcopy *ecp) { struct section *s; Elf_Data *data; GElf_Shdr sh; + const char *image; + size_t sz; s = ecp->shstrtab; @@ -1453,19 +1458,21 @@ set_shstrtab(struct elfcopy *ecp) * which are reserved for this in the beginning of shstrtab. */ if (!(ecp->flags & SYMTAB_EXIST)) { - s->sz -= sizeof(".symtab\0.strtab"); - memmove(s->buf, (char *)s->buf + sizeof(".symtab\0.strtab"), - s->sz); + elftc_string_table_remove(s->strtab, ".symtab"); + elftc_string_table_remove(s->strtab, ".strtab"); } - sh.sh_size = s->sz; + image = elftc_string_table_image(s->strtab, &sz); + s->sz = sz; + + sh.sh_size = sz; if (!gelf_update_shdr(s->os, &sh)) errx(EXIT_FAILURE, "gelf_update_shdr() failed: %s", elf_errmsg(-1)); data->d_align = 1; - data->d_buf = s->buf; - data->d_size = s->sz; + data->d_buf = (void *)(uintptr_t)image; + data->d_size = sz; data->d_off = 0; data->d_type = ELF_T_BYTE; data->d_version = EV_CURRENT; @@ -1589,73 +1596,6 @@ add_gnu_debuglink(struct elfcopy *ecp) STAILQ_INSERT_TAIL(&ecp->v_sadd, sa, sadd_list); ecp->flags |= SEC_ADD; -} - -static void -insert_to_strtab(struct section *t, const char *s) -{ - const char *r; - char *b, *c; - size_t len, slen; - int append; - - if (t->sz == 0) { - t->cap = 512; - if ((t->buf = malloc(t->cap)) == NULL) - err(EXIT_FAILURE, "malloc failed"); - } - - slen = strlen(s); - append = 0; - b = t->buf; - for (c = b; c < b + t->sz;) { - len = strlen(c); - if (!append && len >= slen) { - r = c + (len - slen); - if (strcmp(r, s) == 0) - return; - } else if (len < slen && len != 0) { - r = s + (slen - len); - if (strcmp(c, r) == 0) { - t->sz -= len + 1; - memmove(c, c + len + 1, t->sz - (c - b)); - append = 1; - continue; - } - } - c += len + 1; - } - - while (t->sz + slen + 1 >= t->cap) { - t->cap *= 2; - if ((t->buf = realloc(t->buf, t->cap)) == NULL) - err(EXIT_FAILURE, "realloc failed"); - } - b = t->buf; - strncpy(&b[t->sz], s, slen); - b[t->sz + slen] = '\0'; - t->sz += slen + 1; -} - -static int -lookup_string(struct section *t, const char *s) -{ - const char *b, *c, *r; - size_t len, slen; - - slen = strlen(s); - b = t->buf; - for (c = b; c < b + t->sz;) { - len = strlen(c); - if (len >= slen) { - r = c + (len - slen); - if (strcmp(r, s) == 0) - return (r - b); - } - c += len + 1; - } - - return (-1); } static uint32_t crctable[256] =
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201906041834.x54IY5Qs035508>