github.com/afumu/libc@v0.0.6/musl/src/ldso/dl_iterate_phdr.c (about) 1 #include <elf.h> 2 #include <link.h> 3 #include "libc.h" 4 5 #define AUX_CNT 38 6 7 extern weak hidden const size_t _DYNAMIC[]; 8 9 static int static_dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void *data), void *data) 10 { 11 unsigned char *p; 12 ElfW(Phdr) *phdr, *tls_phdr=0; 13 size_t base = 0; 14 size_t n; 15 struct dl_phdr_info info; 16 size_t i, aux[AUX_CNT] = {0}; 17 18 for (i=0; libc.auxv[i]; i+=2) 19 if (libc.auxv[i]<AUX_CNT) aux[libc.auxv[i]] = libc.auxv[i+1]; 20 21 for (p=(void *)aux[AT_PHDR],n=aux[AT_PHNUM]; n; n--,p+=aux[AT_PHENT]) { 22 phdr = (void *)p; 23 if (phdr->p_type == PT_PHDR) 24 base = aux[AT_PHDR] - phdr->p_vaddr; 25 if (phdr->p_type == PT_DYNAMIC && _DYNAMIC) 26 base = (size_t)_DYNAMIC - phdr->p_vaddr; 27 if (phdr->p_type == PT_TLS) 28 tls_phdr = phdr; 29 } 30 info.dlpi_addr = base; 31 info.dlpi_name = "/proc/self/exe"; 32 info.dlpi_phdr = (void *)aux[AT_PHDR]; 33 info.dlpi_phnum = aux[AT_PHNUM]; 34 info.dlpi_adds = 0; 35 info.dlpi_subs = 0; 36 if (tls_phdr) { 37 info.dlpi_tls_modid = 1; 38 info.dlpi_tls_data = (void *)(base + tls_phdr->p_vaddr); 39 } else { 40 info.dlpi_tls_modid = 0; 41 info.dlpi_tls_data = 0; 42 } 43 return (callback)(&info, sizeof (info), data); 44 } 45 46 weak_alias(static_dl_iterate_phdr, dl_iterate_phdr);