Fixes for builds that require strict X/Open and POSIX compatiblity
Summary:
- Use alternative to MAP_ANONYMOUS for allocating mapped memory if it isn't available
- Use strtok_r instead of strsep as part of getting program path
- Don't try to find the width of a terminal using "struct winsize" and TIOCGWINSZ on POSIX builds. These aren't defined under POSIX (even though some platforms make them available when they shouldn't), so just check if we are doing a X/Open or POSIX compliant build first.
Author: daltenty
Reviewers: hubert.reinterpretcast, xingxue, andusy
Reviewed By: hubert.reinterpretcast
Subscribers: MaskRay, jsji, hiraditya, kristina, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61326
llvm-svn: 360898
diff --git a/llvm/lib/Support/Unix/Memory.inc b/llvm/lib/Support/Unix/Memory.inc
index affdb7e..05c5ccb 100644
--- a/llvm/lib/Support/Unix/Memory.inc
+++ b/llvm/lib/Support/Unix/Memory.inc
@@ -91,9 +91,24 @@
if (NumBytes == 0)
return MemoryBlock();
- int fd = -1;
+ // On platforms that have it, we can use MAP_ANON to get a memory-mapped
+ // page without file backing, but we need a fallback of opening /dev/zero
+ // for strictly POSIX platforms instead.
+ int fd;
+#if defined(MAP_ANON)
+ fd = -1;
+#else
+ fd = open("/dev/zero", O_RDWR);
+ if (fd == -1) {
+ EC = std::error_code(errno, std::generic_category());
+ return MemoryBlock();
+ }
+#endif
- int MMFlags = MAP_PRIVATE | MAP_ANON;
+ int MMFlags = MAP_PRIVATE;
+#if defined(MAP_ANON)
+ MMFlags |= MAP_ANON;
+#endif
int Protect = getPosixProtectionFlags(PFlags);
#if defined(__NetBSD__) && defined(PROT_MPROTECT)
@@ -111,13 +126,24 @@
void *Addr = ::mmap(reinterpret_cast<void *>(Start), NumBytes, Protect,
MMFlags, fd, 0);
if (Addr == MAP_FAILED) {
- if (NearBlock) //Try again without a near hint
+ if (NearBlock) { //Try again without a near hint
+#if !defined(MAP_ANON)
+ close(fd);
+#endif
return allocateMappedMemory(NumBytes, nullptr, PFlags, EC);
+ }
EC = std::error_code(errno, std::generic_category());
+#if !defined(MAP_ANON)
+ close(fd);
+#endif
return MemoryBlock();
}
+#if !defined(MAP_ANON)
+ close(fd);
+#endif
+
MemoryBlock Result;
Result.Address = Addr;
Result.Size = NumBytes;
diff --git a/llvm/lib/Support/Unix/Path.inc b/llvm/lib/Support/Unix/Path.inc
index c2f78e7..359202f 100644
--- a/llvm/lib/Support/Unix/Path.inc
+++ b/llvm/lib/Support/Unix/Path.inc
@@ -132,8 +132,6 @@
static char *
getprogpath(char ret[PATH_MAX], const char *bin)
{
- char *pv, *s, *t;
-
/* First approach: absolute path. */
if (bin[0] == '/') {
if (test_dir(ret, "/", bin) == 0)
@@ -152,18 +150,21 @@
}
/* Third approach: $PATH */
+ char *pv;
if ((pv = getenv("PATH")) == nullptr)
return nullptr;
- s = pv = strdup(pv);
- if (!pv)
+ char *s = strdup(pv);
+ if (!s)
return nullptr;
- while ((t = strsep(&s, ":")) != nullptr) {
+ char *state;
+ for (char *t = strtok_r(s, ":", &state); t != nullptr;
+ t = strtok_r(nullptr, ":", &state)) {
if (test_dir(ret, t, bin) == 0) {
- free(pv);
+ free(s);
return ret;
}
}
- free(pv);
+ free(s);
return nullptr;
}
#endif // __FreeBSD__ || __NetBSD__ || __FreeBSD_kernel__
diff --git a/llvm/lib/Support/Unix/Process.inc b/llvm/lib/Support/Unix/Process.inc
index 78c1234..4115ee3 100644
--- a/llvm/lib/Support/Unix/Process.inc
+++ b/llvm/lib/Support/Unix/Process.inc
@@ -291,7 +291,8 @@
unsigned Columns = 0;
-#if defined(HAVE_SYS_IOCTL_H) && defined(HAVE_TERMIOS_H)
+#if defined(HAVE_SYS_IOCTL_H) && defined(HAVE_TERMIOS_H) \
+ && !(defined(_XOPEN_SOURCE) || defined(_POSIX_C_SOURCE))
// Try to determine the width of the terminal.
struct winsize ws;
if (ioctl(FileID, TIOCGWINSZ, &ws) == 0)