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authorDenis Vlasenko <vda.linux@googlemail.com>2009-01-10 21:02:48 +0000
committerDenis Vlasenko <vda.linux@googlemail.com>2009-01-10 21:02:48 +0000
commit27d501fdbf0c6932e6170e8dece4d178d912bf94 (patch)
tree054224e4ebe3ee638fb5b8d28e9873fbcd13c537 /ldso/ldso/ldso.c
parent1c778b7cfac9228aa6dbd3c7d3b1417887fc3031 (diff)
simple optimizations and style fixes in dynamic loading
text data bss dec hex filename - 16709 240 92 17041 4291 lib/ld-uClibc.so + 16634 236 92 16962 4242 lib/ld-uClibc.so - 4602 344 4 4950 1356 lib/libdl-0.9.30-svn.so + 4571 328 4 4903 1327 lib/libdl-0.9.30-svn.so - 4602 344 4 4950 1356 lib/libdl.so + 4571 328 4 4903 1327 lib/libdl.so
Diffstat (limited to 'ldso/ldso/ldso.c')
-rw-r--r--ldso/ldso/ldso.c264
1 files changed, 134 insertions, 130 deletions
diff --git a/ldso/ldso/ldso.c b/ldso/ldso/ldso.c
index f631fd983..4dcd99bfe 100644
--- a/ldso/ldso/ldso.c
+++ b/ldso/ldso/ldso.c
@@ -42,24 +42,25 @@
#include LDSO_ELFINTERP
/* Global variables used within the shared library loader */
-char *_dl_library_path = 0; /* Where we look for libraries */
-char *_dl_preload = 0; /* Things to be loaded before the libs */
-char *_dl_ldsopath = 0; /* Location of the shared lib loader */
-int _dl_secure = 1; /* Are we dealing with setuid stuff? */
+char *_dl_library_path = NULL; /* Where we look for libraries */
+char *_dl_preload = NULL; /* Things to be loaded before the libs */
+char *_dl_ldsopath = NULL; /* Location of the shared lib loader */
int _dl_errno = 0; /* We can't use the real errno in ldso */
size_t _dl_pagesize = 0; /* Store the page size for use later */
struct r_debug *_dl_debug_addr = NULL; /* Used to communicate with the gdb debugger */
void *(*_dl_malloc_function) (size_t size) = NULL;
void (*_dl_free_function) (void *p) = NULL;
+static int _dl_secure = 1; /* Are we dealing with setuid stuff? */
+
#ifdef __SUPPORT_LD_DEBUG__
-char *_dl_debug = 0;
-char *_dl_debug_symbols = 0;
-char *_dl_debug_move = 0;
-char *_dl_debug_reloc = 0;
-char *_dl_debug_detail = 0;
-char *_dl_debug_nofixups = 0;
-char *_dl_debug_bindings = 0;
+char *_dl_debug = NULL;
+char *_dl_debug_symbols = NULL;
+char *_dl_debug_move = NULL;
+char *_dl_debug_reloc = NULL;
+char *_dl_debug_detail = NULL;
+char *_dl_debug_nofixups = NULL;
+char *_dl_debug_bindings = NULL;
int _dl_debug_file = 2;
#endif
@@ -69,8 +70,6 @@ const char *_dl_progname = UCLIBC_LDSO; /* The name of the executable being
#include "dl-startup.c"
#include "dl-symbols.c"
#include "dl-array.c"
-/* Forward function declarations */
-static int _dl_suid_ok(void);
/*
* This stub function is used by some debuggers. The idea is that they
@@ -88,8 +87,8 @@ void _dl_debug_state(void)
}
rtld_hidden_def(_dl_debug_state);
-static unsigned char *_dl_malloc_addr = 0; /* Lets _dl_malloc use the already allocated memory page */
-static unsigned char *_dl_mmap_zero = 0; /* Also used by _dl_malloc */
+static unsigned char *_dl_malloc_addr = NULL; /* Lets _dl_malloc use the already allocated memory page */
+static unsigned char *_dl_mmap_zero = NULL; /* Also used by _dl_malloc */
static struct elf_resolve **init_fini_list;
static unsigned int nlist; /* # items in init_fini_list */
@@ -110,6 +109,118 @@ uintptr_t __guard attribute_relro;
# endif
#endif
+char *_dl_getenv(const char *symbol, char **envp)
+{
+ char *pnt;
+ const char *pnt1;
+
+ while ((pnt = *envp++)) {
+ pnt1 = symbol;
+ while (*pnt && *pnt == *pnt1)
+ pnt1++, pnt++;
+ if (!*pnt || *pnt != '=' || *pnt1)
+ continue;
+ return pnt + 1;
+ }
+ return 0;
+}
+
+void _dl_unsetenv(const char *symbol, char **envp)
+{
+ char *pnt;
+ const char *pnt1;
+ char **newenvp = envp;
+
+ for (pnt = *envp; pnt; pnt = *++envp) {
+ pnt1 = symbol;
+ while (*pnt && *pnt == *pnt1)
+ pnt1++, pnt++;
+ if (!*pnt || *pnt != '=' || *pnt1)
+ *newenvp++ = *envp;
+ }
+ *newenvp++ = *envp;
+ return;
+}
+
+static int _dl_suid_ok(void)
+{
+ __kernel_uid_t uid, euid;
+ __kernel_gid_t gid, egid;
+
+ uid = _dl_getuid();
+ euid = _dl_geteuid();
+ gid = _dl_getgid();
+ egid = _dl_getegid();
+
+ if (uid == euid && gid == egid) {
+ return 1;
+ }
+ return 0;
+}
+
+void *_dl_malloc(size_t size)
+{
+ void *retval;
+
+#if 0
+ _dl_debug_early("request for %d bytes\n", size);
+#endif
+
+ if (_dl_malloc_function)
+ return (*_dl_malloc_function) (size);
+
+ if (_dl_malloc_addr - _dl_mmap_zero + size > _dl_pagesize) {
+ size_t rounded_size;
+
+ /* Since the above assumes we get a full page even if
+ we request less than that, make sure we request a
+ full page, since uClinux may give us less than than
+ a full page. We might round even
+ larger-than-a-page sizes, but we end up never
+ reusing _dl_mmap_zero/_dl_malloc_addr in that case,
+ so we don't do it.
+
+ The actual page size doesn't really matter; as long
+ as we're self-consistent here, we're safe. */
+ if (size < _dl_pagesize)
+ rounded_size = (size + ADDR_ALIGN) & _dl_pagesize;
+ else
+ rounded_size = size;
+
+ _dl_debug_early("mmapping more memory\n");
+ _dl_mmap_zero = _dl_malloc_addr = _dl_mmap((void *) 0, rounded_size,
+ PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (_dl_mmap_check_error(_dl_mmap_zero)) {
+ _dl_dprintf(_dl_debug_file, "%s: mmap of a spare page failed!\n", _dl_progname);
+ _dl_exit(20);
+ }
+ }
+ retval = _dl_malloc_addr;
+ _dl_malloc_addr += size;
+
+ /*
+ * Align memory to DL_MALLOC_ALIGN byte boundary. Some
+ * platforms require this, others simply get better
+ * performance.
+ */
+ _dl_malloc_addr = (unsigned char *) (((unsigned long) _dl_malloc_addr + DL_MALLOC_ALIGN - 1) & ~(DL_MALLOC_ALIGN - 1));
+ return retval;
+}
+
+static void *_dl_zalloc(size_t size)
+{
+ void *p = _dl_malloc(size);
+ if (p)
+ _dl_memset(p, 0, size);
+ return p;
+}
+
+void _dl_free (void *p)
+{
+ if (_dl_free_function)
+ (*_dl_free_function) (p);
+}
+
static void __attribute__ ((destructor)) __attribute_used__ _dl_fini(void)
{
unsigned int i;
@@ -158,7 +269,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
* setup so we can use _dl_dprintf() to print debug noise
* instead of the SEND_STDERR macros used in dl-startup.c */
- _dl_memset(app_tpnt, 0x00, sizeof(*app_tpnt));
+ _dl_memset(app_tpnt, 0, sizeof(*app_tpnt));
/* Store the page size for later use */
_dl_pagesize = (auxvt[AT_PAGESZ].a_un.a_val) ? (size_t) auxvt[AT_PAGESZ].a_un.a_val : PAGE_SIZE;
@@ -219,7 +330,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
do {
_dl_unsetenv (nextp, envp);
/* We could use rawmemchr but this need not be fast. */
- nextp = (char *) _dl_strchr(nextp, '\0') + 1;
+ nextp = _dl_strchr(nextp, '\0') + 1;
} while (*nextp != '\0');
_dl_preload = NULL;
_dl_library_path = NULL;
@@ -269,8 +380,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
* This is used by gdb to locate the chain of shared libraries that are
* currently loaded.
*/
- debug_addr = _dl_malloc(sizeof(struct r_debug));
- _dl_memset(debug_addr, 0, sizeof(struct r_debug));
+ debug_addr = _dl_zalloc(sizeof(struct r_debug));
ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {
@@ -324,7 +434,7 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
_dl_loaded_modules->libtype = elf_executable;
_dl_loaded_modules->ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_val;
_dl_loaded_modules->n_phent = auxvt[AT_PHNUM].a_un.a_val;
- _dl_symbol_tables = rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
+ _dl_symbol_tables = rpnt = _dl_malloc(sizeof(struct dyn_elf));
_dl_memset(rpnt, 0, sizeof(struct dyn_elf));
rpnt->dyn = _dl_loaded_modules;
app_tpnt->mapaddr = app_mapaddr;
@@ -389,14 +499,14 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
len1 = _dl_strlen(dl_debug_output);
len2 = _dl_strlen(tmp1);
- filename = _dl_malloc(len1+len2+2);
+ filename = _dl_malloc(len1 + len2 + 2);
if (filename) {
_dl_strcpy (filename, dl_debug_output);
filename[len1] = '.';
_dl_strcpy (&filename[len1+1], tmp1);
- _dl_debug_file= _dl_open(filename, O_WRONLY|O_CREAT, 0644);
+ _dl_debug_file = _dl_open(filename, O_WRONLY|O_CREAT, 0644);
if (_dl_debug_file < 0) {
_dl_debug_file = 2;
_dl_dprintf(_dl_debug_file, "can't open file: '%s'\n",filename);
@@ -711,13 +821,11 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
tpnt->usage_count++;
tpnt->symbol_scope = _dl_symbol_tables;
if (rpnt) {
- rpnt->next = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
- _dl_memset(rpnt->next, 0, sizeof(struct dyn_elf));
+ rpnt->next = _dl_zalloc(sizeof(struct dyn_elf));
rpnt->next->prev = rpnt;
rpnt = rpnt->next;
} else {
- rpnt = (struct dyn_elf *) _dl_malloc(sizeof(struct dyn_elf));
- _dl_memset(rpnt, 0, sizeof(struct dyn_elf));
+ rpnt = _dl_zalloc(sizeof(struct dyn_elf));
}
rpnt->dyn = tpnt;
tpnt->rtld_flags = RTLD_NOW | RTLD_GLOBAL; /* Must not be LAZY */
@@ -840,109 +948,5 @@ void _dl_get_ready_to_run(struct elf_resolve *tpnt, DL_LOADADDR_TYPE load_addr,
_dl_debug_state();
}
-char *_dl_getenv(const char *symbol, char **envp)
-{
- char *pnt;
- const char *pnt1;
-
- while ((pnt = *envp++)) {
- pnt1 = symbol;
- while (*pnt && *pnt == *pnt1)
- pnt1++, pnt++;
- if (!*pnt || *pnt != '=' || *pnt1)
- continue;
- return pnt + 1;
- }
- return 0;
-}
-
-void _dl_unsetenv(const char *symbol, char **envp)
-{
- char *pnt;
- const char *pnt1;
- char **newenvp = envp;
-
- for (pnt = *envp; pnt; pnt = *++envp) {
- pnt1 = symbol;
- while (*pnt && *pnt == *pnt1)
- pnt1++, pnt++;
- if (!*pnt || *pnt != '=' || *pnt1)
- *newenvp++ = *envp;
- }
- *newenvp++ = *envp;
- return;
-}
-
-static int _dl_suid_ok(void)
-{
- __kernel_uid_t uid, euid;
- __kernel_gid_t gid, egid;
-
- uid = _dl_getuid();
- euid = _dl_geteuid();
- gid = _dl_getgid();
- egid = _dl_getegid();
-
- if (uid == euid && gid == egid) {
- return 1;
- }
- return 0;
-}
-
-void *_dl_malloc(size_t size)
-{
- void *retval;
-
-#if 0
- _dl_debug_early("request for %d bytes\n", size);
-#endif
-
- if (_dl_malloc_function)
- return (*_dl_malloc_function) (size);
-
- if (_dl_malloc_addr - _dl_mmap_zero + size > _dl_pagesize) {
- size_t rounded_size;
-
- /* Since the above assumes we get a full page even if
- we request less than that, make sure we request a
- full page, since uClinux may give us less than than
- a full page. We might round even
- larger-than-a-page sizes, but we end up never
- reusing _dl_mmap_zero/_dl_malloc_addr in that case,
- so we don't do it.
-
- The actual page size doesn't really matter; as long
- as we're self-consistent here, we're safe. */
- if (size < _dl_pagesize)
- rounded_size = (size + ADDR_ALIGN) & _dl_pagesize;
- else
- rounded_size = size;
-
- _dl_debug_early("mmapping more memory\n");
- _dl_mmap_zero = _dl_malloc_addr = _dl_mmap((void *) 0, rounded_size,
- PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if (_dl_mmap_check_error(_dl_mmap_zero)) {
- _dl_dprintf(_dl_debug_file, "%s: mmap of a spare page failed!\n", _dl_progname);
- _dl_exit(20);
- }
- }
- retval = _dl_malloc_addr;
- _dl_malloc_addr += size;
-
- /*
- * Align memory to DL_MALLOC_ALIGN byte boundary. Some
- * platforms require this, others simply get better
- * performance.
- */
- _dl_malloc_addr = (unsigned char *) (((unsigned long) _dl_malloc_addr + DL_MALLOC_ALIGN - 1) & ~(DL_MALLOC_ALIGN - 1));
- return retval;
-}
-
-void _dl_free (void *p)
-{
- if (_dl_free_function)
- (*_dl_free_function) (p);
-}
-
#include "dl-hash.c"
#include "dl-elf.c"