dump: Split elf header functions into prepare and write
Let's split the write from the modification of the elf header so we
can consolidate the write of the data in one function.
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220811121111.9878-8-frankja@linux.ibm.com>
diff --git a/dump/dump.c b/dump/dump.c
index d82cc46..8a2a97a 100644
--- a/dump/dump.c
+++ b/dump/dump.c
@@ -131,7 +131,7 @@
return 0;
}
-static void write_elf64_header(DumpState *s, Error **errp)
+static void prepare_elf64_header(DumpState *s, Elf64_Ehdr *elf_header)
{
/*
* phnum in the elf header is 16 bit, if we have more segments we
@@ -139,34 +139,27 @@
* special section.
*/
uint16_t phnum = MIN(s->phdr_num, PN_XNUM);
- Elf64_Ehdr elf_header;
- int ret;
- memset(&elf_header, 0, sizeof(Elf64_Ehdr));
- memcpy(&elf_header, ELFMAG, SELFMAG);
- elf_header.e_ident[EI_CLASS] = ELFCLASS64;
- elf_header.e_ident[EI_DATA] = s->dump_info.d_endian;
- elf_header.e_ident[EI_VERSION] = EV_CURRENT;
- elf_header.e_type = cpu_to_dump16(s, ET_CORE);
- elf_header.e_machine = cpu_to_dump16(s, s->dump_info.d_machine);
- elf_header.e_version = cpu_to_dump32(s, EV_CURRENT);
- elf_header.e_ehsize = cpu_to_dump16(s, sizeof(elf_header));
- elf_header.e_phoff = cpu_to_dump64(s, s->phdr_offset);
- elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr));
- elf_header.e_phnum = cpu_to_dump16(s, phnum);
+ memset(elf_header, 0, sizeof(Elf64_Ehdr));
+ memcpy(elf_header, ELFMAG, SELFMAG);
+ elf_header->e_ident[EI_CLASS] = ELFCLASS64;
+ elf_header->e_ident[EI_DATA] = s->dump_info.d_endian;
+ elf_header->e_ident[EI_VERSION] = EV_CURRENT;
+ elf_header->e_type = cpu_to_dump16(s, ET_CORE);
+ elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine);
+ elf_header->e_version = cpu_to_dump32(s, EV_CURRENT);
+ elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header));
+ elf_header->e_phoff = cpu_to_dump64(s, s->phdr_offset);
+ elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr));
+ elf_header->e_phnum = cpu_to_dump16(s, phnum);
if (s->shdr_num) {
- elf_header.e_shoff = cpu_to_dump64(s, s->shdr_offset);
- elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr));
- elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num);
- }
-
- ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s);
- if (ret < 0) {
- error_setg_errno(errp, -ret, "dump: failed to write elf header");
+ elf_header->e_shoff = cpu_to_dump64(s, s->shdr_offset);
+ elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr));
+ elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num);
}
}
-static void write_elf32_header(DumpState *s, Error **errp)
+static void prepare_elf32_header(DumpState *s, Elf32_Ehdr *elf_header)
{
/*
* phnum in the elf header is 16 bit, if we have more segments we
@@ -174,28 +167,45 @@
* special section.
*/
uint16_t phnum = MIN(s->phdr_num, PN_XNUM);
- Elf32_Ehdr elf_header;
+
+ memset(elf_header, 0, sizeof(Elf32_Ehdr));
+ memcpy(elf_header, ELFMAG, SELFMAG);
+ elf_header->e_ident[EI_CLASS] = ELFCLASS32;
+ elf_header->e_ident[EI_DATA] = s->dump_info.d_endian;
+ elf_header->e_ident[EI_VERSION] = EV_CURRENT;
+ elf_header->e_type = cpu_to_dump16(s, ET_CORE);
+ elf_header->e_machine = cpu_to_dump16(s, s->dump_info.d_machine);
+ elf_header->e_version = cpu_to_dump32(s, EV_CURRENT);
+ elf_header->e_ehsize = cpu_to_dump16(s, sizeof(elf_header));
+ elf_header->e_phoff = cpu_to_dump32(s, s->phdr_offset);
+ elf_header->e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr));
+ elf_header->e_phnum = cpu_to_dump16(s, phnum);
+ if (s->shdr_num) {
+ elf_header->e_shoff = cpu_to_dump32(s, s->shdr_offset);
+ elf_header->e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr));
+ elf_header->e_shnum = cpu_to_dump16(s, s->shdr_num);
+ }
+}
+
+static void write_elf_header(DumpState *s, Error **errp)
+{
+ Elf32_Ehdr elf32_header;
+ Elf64_Ehdr elf64_header;
+ size_t header_size;
+ void *header_ptr;
int ret;
- memset(&elf_header, 0, sizeof(Elf32_Ehdr));
- memcpy(&elf_header, ELFMAG, SELFMAG);
- elf_header.e_ident[EI_CLASS] = ELFCLASS32;
- elf_header.e_ident[EI_DATA] = s->dump_info.d_endian;
- elf_header.e_ident[EI_VERSION] = EV_CURRENT;
- elf_header.e_type = cpu_to_dump16(s, ET_CORE);
- elf_header.e_machine = cpu_to_dump16(s, s->dump_info.d_machine);
- elf_header.e_version = cpu_to_dump32(s, EV_CURRENT);
- elf_header.e_ehsize = cpu_to_dump16(s, sizeof(elf_header));
- elf_header.e_phoff = cpu_to_dump32(s, s->phdr_offset);
- elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr));
- elf_header.e_phnum = cpu_to_dump16(s, phnum);
- if (s->shdr_num) {
- elf_header.e_shoff = cpu_to_dump32(s, s->shdr_offset);
- elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr));
- elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num);
+ if (dump_is_64bit(s)) {
+ prepare_elf64_header(s, &elf64_header);
+ header_size = sizeof(elf64_header);
+ header_ptr = &elf64_header;
+ } else {
+ prepare_elf32_header(s, &elf32_header);
+ header_size = sizeof(elf32_header);
+ header_ptr = &elf32_header;
}
- ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s);
+ ret = fd_write_vmcore(header_ptr, header_size, s);
if (ret < 0) {
error_setg_errno(errp, -ret, "dump: failed to write elf header");
}
@@ -564,11 +574,7 @@
*/
/* write elf header to vmcore */
- if (dump_is_64bit(s)) {
- write_elf64_header(s, errp);
- } else {
- write_elf32_header(s, errp);
- }
+ write_elf_header(s, errp);
if (*errp) {
return;
}
