Make improvements

- Implement openpty()
- Add `--assimilate` flag to APE bootloader
- Restore Linux vDSO clock_gettime() support
- Use `$(APE_NO_MODIFY_SELF)` on more programs

tool/decode/elf.c

@@ -157,7 +157,8 @@ static void printelfsectionheader(int i, char *shstrtab) {
 
 static void printelfsectionheaders(void) {
   Elf64_Half i;
-  char *shstrtab = GetElfSectionNameStringTable(elf, st->st_size);
+  char *shstrtab;
+  shstrtab = GetElfSectionNameStringTable(elf, st->st_size);
   if (shstrtab) {
     printf("\n");
     printf("\t.org\t%#x\n", elf->e_shoff);
@@ -341,7 +342,6 @@ int main(int argc, char *argv[]) {
     fprintf(stderr, "error: not an elf executable: %'s\n", path);
     exit(1);
   }
-  elf = (Elf64_Ehdr *)getauxval(AT_SYSINFO_EHDR);
   startfile();
   printelfehdr();
   printelfsegmentheaders();

tool/viz/vdsosyms.c

@@ -0,0 +1,166 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/strace.internal.h"
+#include "libc/elf/def.h"
+#include "libc/elf/scalar.h"
+#include "libc/elf/struct/ehdr.h"
+#include "libc/elf/struct/phdr.h"
+#include "libc/elf/struct/sym.h"
+#include "libc/elf/struct/verdaux.h"
+#include "libc/elf/struct/verdef.h"
+#include "libc/intrin/kprintf.h"
+#include "libc/runtime/runtime.h"
+#include "libc/sysv/consts/auxv.h"
+
+static inline void PrintDsoSymbolVersions(Elf64_Verdef *vd, int sym,
+                                          char *strtab) {
+  Elf64_Verdaux *aux;
+  for (;; vd = (Elf64_Verdef *)((char *)vd + vd->vd_next)) {
+    if (!(vd->vd_flags & VER_FLG_BASE) &&
+        (vd->vd_ndx & 0x7fff) == (sym & 0x7fff)) {
+      aux = (Elf64_Verdaux *)((char *)vd + vd->vd_aux);
+      kprintf(" %s", strtab + aux->vda_name);
+    }
+    if (!vd->vd_next) {
+      break;
+    }
+  }
+}
+
+int PrintVdsoSymbols(void) {
+  void *p;
+  size_t i;
+  Elf64_Ehdr *ehdr;
+  Elf64_Phdr *phdr;
+  char *strtab = 0;
+  size_t *dyn, base;
+  unsigned long *ap;
+  Elf64_Sym *symtab = 0;
+  uint16_t *versym = 0;
+  Elf_Symndx *hashtab = 0;
+  Elf64_Verdef *verdef = 0;
+  const char *typename, *bindname;
+
+  for (ehdr = 0, ap = __auxv; ap[0]; ap += 2) {
+    if (ap[0] == AT_SYSINFO_EHDR) {
+      ehdr = (void *)ap[1];
+      break;
+    }
+  }
+  if (!ehdr) {
+    kprintf("error: AT_SYSINFO_EHDR not found\n");
+    return 1;
+  }
+
+  phdr = (void *)((char *)ehdr + ehdr->e_phoff);
+  for (base = -1, dyn = 0, i = 0; i < ehdr->e_phnum;
+       i++, phdr = (void *)((char *)phdr + ehdr->e_phentsize)) {
+    switch (phdr->p_type) {
+      case PT_LOAD:
+        // modern linux uses the base address zero, but elders
+        // e.g. rhel7 uses the base address 0xffffffffff700000
+        base = (size_t)ehdr + phdr->p_offset - phdr->p_vaddr;
+        break;
+      case PT_DYNAMIC:
+        dyn = (void *)((char *)ehdr + phdr->p_offset);
+        break;
+      default:
+        break;
+    }
+  }
+  if (!dyn || base == -1) {
+    kprintf("error: missing program headers\n");
+    return 2;
+  }
+
+  for (i = 0; dyn[i]; i += 2) {
+    p = (void *)(base + dyn[i + 1]);
+    switch (dyn[i]) {
+      case DT_STRTAB:
+        strtab = p;
+        break;
+      case DT_SYMTAB:
+        symtab = p;
+        break;
+      case DT_HASH:
+        hashtab = p;
+        break;
+      case DT_VERSYM:
+        versym = p;
+        break;
+      case DT_VERDEF:
+        verdef = p;
+        break;
+    }
+  }
+  if (!verdef) {
+    versym = 0;
+  }
+
+  if (!strtab || !symtab || !hashtab) {
+    kprintf("error: strtab/symtab/hashtab not found\n");
+    return 3;
+  }
+
+  for (i = 0; i < hashtab[1]; i++) {
+    if (!symtab[i].st_shndx) {
+      continue;
+    }
+
+    switch (ELF64_ST_BIND(symtab[i].st_info)) {
+      case STB_LOCAL:
+        bindname = "locl";
+        break;
+      case STB_GLOBAL:
+        bindname = "glob";
+        break;
+      case STB_WEAK:
+        bindname = "weak";
+        break;
+      default:
+        bindname = "????";
+        break;
+    }
+
+    switch (ELF64_ST_TYPE(symtab[i].st_info)) {
+      case STT_FUNC:
+        typename = "func";
+        break;
+      case STT_OBJECT:
+        typename = " obj";
+        break;
+      case STT_NOTYPE:
+        typename = "none";
+        break;
+      default:
+        typename = "????";
+        break;
+    }
+
+    kprintf("%s %s %-40s", bindname, typename, strtab + symtab[i].st_name);
+    PrintDsoSymbolVersions(verdef, versym[i], strtab);
+    kprintf("\n");
+  }
+
+  return 0;
+}
+
+int main(int argc, char *argv[]) {
+  return PrintVdsoSymbols();
+}