Initial import

2025-05-28 00:02:28 +00:00 · 2020-06-15 07:18:57 -07:00 · 2020-06-15 07:18:57 -07:00 · c91b3c5006
commit c91b3c5006
14915 changed files with 590219 additions and 0 deletions
--- a/libc/elf/elf.h
+++ b/libc/elf/elf.h
@ -0,0 +1,120 @@
+#ifndef COSMOPOLITAN_LIBC_ELF_H_
+#define COSMOPOLITAN_LIBC_ELF_H_
+#include "libc/bits/safemacros.h"
+#include "libc/elf/def.h"
+#include "libc/elf/struct/ehdr.h"
+#include "libc/elf/struct/phdr.h"
+#include "libc/elf/struct/shdr.h"
+#include "libc/elf/struct/sym.h"
+#include "libc/limits.h"
+#include "libc/runtime/runtime.h"
+#include "libc/str/str.h"
+#if !(__ASSEMBLER__ + __LINKER__ + 0)
+COSMOPOLITAN_C_START_
+
+/*───────────────────────────────────────────────────────────────────────────│─╗
+│ cosmopolitan § executable & linkable format                              ─╬─│┼
+╚────────────────────────────────────────────────────────────────────────────│*/
+
+struct MappedFile;
+
+Elf64_Ehdr *mapelfread(const char *filename, struct MappedFile *mf);
+char *getelfstringtable(const Elf64_Ehdr *elf, size_t mapsize);
+Elf64_Sym *getelfsymboltable(const Elf64_Ehdr *elf, size_t mapsize,
+                             Elf64_Xword *out_count);
+Elf64_Shdr *getelfsectionbyaddress(const Elf64_Ehdr *elf, size_t mapsize,
+                                   void *addr);
+
+forceinline void checkelfaddress(const Elf64_Ehdr *elf, size_t mapsize,
+                                 intptr_t addr, size_t addrsize) {
+#if !(TRUSTWORTHY + ELF_TRUSTWORTHY + 0)
+  if (addr < (intptr_t)elf || addr + addrsize > (intptr_t)elf + mapsize) {
+    abort();
+  }
+#endif
+}
+
+static inline bool iself64binary(const Elf64_Ehdr *elf, size_t mapsize) {
+  return mapsize >= sizeof(Elf64_Ehdr) &&
+         memcmp(elf->e_ident, ELFMAG, 4) == 0 &&
+         (elf->e_ident[EI_CLASS] == ELFCLASSNONE ||
+          elf->e_ident[EI_CLASS] == ELFCLASS64);
+}
+
+static inline bool iselfsymbolcontent(const Elf64_Sym *sym) {
+  return sym->st_size > 0 && (ELF64_ST_TYPE(sym->st_info) == STT_FUNC ||
+                              ELF64_ST_TYPE(sym->st_info) == STT_OBJECT);
+}
+
+static inline Elf64_Phdr *getelfsegmentheaderaddress(const Elf64_Ehdr *elf,
+                                                     size_t mapsize,
+                                                     unsigned i) {
+  intptr_t addr =
+      ((intptr_t)elf + (intptr_t)elf->e_phoff + (intptr_t)elf->e_phentsize * i);
+  checkelfaddress(elf, mapsize, addr, elf->e_phentsize);
+  return (Elf64_Phdr *)addr;
+}
+
+static inline Elf64_Shdr *getelfsectionheaderaddress(const Elf64_Ehdr *elf,
+                                                     size_t mapsize,
+                                                     Elf64_Half i) {
+  intptr_t addr =
+      ((intptr_t)elf + (intptr_t)elf->e_shoff + (intptr_t)elf->e_shentsize * i);
+  checkelfaddress(elf, mapsize, addr, elf->e_shentsize);
+  return (Elf64_Shdr *)addr;
+}
+
+static inline void *getelfsectionaddress(const Elf64_Ehdr *elf, size_t mapsize,
+                                         const Elf64_Shdr *shdr) {
+  intptr_t addr = (intptr_t)elf + (intptr_t)shdr->sh_offset;
+  intptr_t size = (intptr_t)shdr->sh_size;
+  checkelfaddress(elf, mapsize, addr, size);
+  return (void *)addr;
+}
+
+static inline char *getelfsectionnamestringtable(const Elf64_Ehdr *elf,
+                                                 size_t mapsize) {
+  if (!elf->e_shoff || !elf->e_shentsize) return NULL;
+  return getelfsectionaddress(
+      elf, mapsize, getelfsectionheaderaddress(elf, mapsize, elf->e_shstrndx));
+}
+
+static inline void getelfvirtualaddressrange(const Elf64_Ehdr *elf,
+                                             size_t elfsize,
+                                             intptr_t *out_start,
+                                             intptr_t *out_end) {
+  intptr_t start = INTPTR_MAX;
+  intptr_t end = 0;
+  for (unsigned i = 0; i < elf->e_phnum; ++i) {
+    Elf64_Phdr *phdr = getelfsegmentheaderaddress(elf, elfsize, i);
+    if (phdr->p_type != PT_LOAD) continue;
+    intptr_t pstart = phdr->p_vaddr;
+    intptr_t pend = phdr->p_vaddr + phdr->p_memsz;
+    if (pstart < start) start = pstart;
+    if (pend > end) end = pend;
+  }
+  if (out_start) *out_start = start;
+  if (out_end) *out_end = end;
+}
+
+static inline char *getelfstring(const Elf64_Ehdr *elf, size_t mapsize,
+                                 const char *strtab, Elf64_Word rva) {
+  intptr_t addr = (intptr_t)strtab + rva;
+#if !(TRUSTWORTHY + ELF_TRUSTWORTHY + 0)
+  checkelfaddress(elf, mapsize, addr, 0);
+  checkelfaddress(elf, mapsize, addr,
+                  strnlen((char *)addr, (intptr_t)elf + mapsize - addr) + 1);
+#endif
+  return (char *)addr;
+}
+
+static inline const char *getelfsectionname(const Elf64_Ehdr *elf,
+                                            size_t mapsize, Elf64_Shdr *shdr) {
+  if (!elf || !shdr) return NULL;
+  return getelfstring(elf, mapsize, getelfsectionnamestringtable(elf, mapsize),
+                      shdr->sh_name);
+}
+
+COSMOPOLITAN_C_END_
+#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
+#endif /* COSMOPOLITAN_LIBC_ELF_H_ */