[libc] Give more functions restrict qualifiers (NFC)

[AtariDreams]

strsep, strtok_r, strlcpy, and strlcat take restricted pointers as parameters.
Add the restrict qualifiers to them.

Sources:
https://man7.org/linux/man-pages/man3/strsep.3.html
https://man7.org/linux/man-pages/man3/strtok_r.3.html
https://man.freebsd.org/cgi/man.cgi?strlcpy

[llvmbot]

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Author: AtariDreams (AtariDreams)

Changes

strsep has restrict qualifiers, as well as strtok_r. Add the restrict qualifiers to them.

Source: https://man7.org/linux/man-pages/man3/strsep.3.html

---

Full diff: https://github.com/llvm/llvm-project/pull/78061.diff

4 Files Affected:

• (modified) clang/test/Analysis/Inputs/system-header-simulator.h (+3-3)
• (modified) clang/test/Analysis/string.c (+2-2)
• (modified) libc/src/string/strsep.cpp (+1-1)
• (modified) libc/src/string/strsep.h (+1-1)

diff --git a/clang/test/Analysis/Inputs/system-header-simulator.h b/clang/test/Analysis/Inputs/system-header-simulator.h
index cd7ac616bcc67f..5f969adfdd92cd 100644
--- a/clang/test/Analysis/Inputs/system-header-simulator.h
+++ b/clang/test/Analysis/Inputs/system-header-simulator.h
@@ -71,9 +71,9 @@ int fflush(FILE *stream);
 size_t strlen(const char *);
 
 char *strcpy(char *restrict, const char *restrict);
-char *strncpy(char *dst, const char *src, size_t n);
-char *strsep(char **stringp, const char *delim);
-void *memcpy(void *dst, const void *src, size_t n);
+char *strncpy(char *restrict dst, const char * restrict src, size_t n);
+char *strsep(char ** restrict stringp, const char * restrict delim);
+void *memcpy(void * restrict dst, const void * restrict src, size_t n);
 void *memset(void *s, int c, size_t n);
 
 typedef unsigned long __darwin_pthread_key_t;
diff --git a/clang/test/Analysis/string.c b/clang/test/Analysis/string.c
index d47de9db8228e5..85232624160c06 100644
--- a/clang/test/Analysis/string.c
+++ b/clang/test/Analysis/string.c
@@ -71,7 +71,7 @@ void clang_analyzer_eval(int);
 int scanf(const char *restrict format, ...);
 void *malloc(size_t);
 void free(void *);
-void *memcpy(void *dest, const void *src, size_t n);
+void *memcpy(void *restrict dest, const void *restrict src, size_t n);
 
 //===----------------------------------------------------------------------===
 // strlen()
@@ -1252,7 +1252,7 @@ int strncasecmp_null_argument(char *a, size_t n) {
 // strsep()
 //===----------------------------------------------------------------------===
 
-char *strsep(char **stringp, const char *delim);
+char *strsep(char ** restrict stringp, const char * restrict delim);
 
 void strsep_null_delim(char *s) {
   strsep(&s, NULL); // expected-warning{{Null pointer passed as 2nd argument to strsep()}}
diff --git a/libc/src/string/strsep.cpp b/libc/src/string/strsep.cpp
index edd2cf07e20a45..ce74223ee7721d 100644
--- a/libc/src/string/strsep.cpp
+++ b/libc/src/string/strsep.cpp
@@ -12,7 +12,7 @@
 
 namespace LIBC_NAMESPACE {
 
-LLVM_LIBC_FUNCTION(char *, strsep, (char **stringp, const char *delim)) {
+LLVM_LIBC_FUNCTION(char *, strsep, (char ** __restrict stringp, const char * __restrict delim)) {
   if (!*stringp)
     return nullptr;
   return internal::string_token<false>(*stringp, delim, stringp);
diff --git a/libc/src/string/strsep.h b/libc/src/string/strsep.h
index 48f55a899d7f33..d0a22f4af89119 100644
--- a/libc/src/string/strsep.h
+++ b/libc/src/string/strsep.h
@@ -11,7 +11,7 @@
 
 namespace LIBC_NAMESPACE {
 
-char *strsep(char **stringp, const char *delim);
+char *strsep(char ** __restrict stringp, const char * __restrict delim);
 
 } // namespace LIBC_NAMESPACE
 

[lntue]

LGTM for the libc part.
Thanks for adding the missing qualifiers! They were specified in our own generated header but not in the implementation: https://github.com/llvm/llvm-project/blob/main/libc/spec/bsd_ext.td#L21

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[AtariDreams]

@lntue Do you think this PR is acceptable?

[jhuber6]

LLVM changes look unrelated, it was originally copied from OpenBSD it seems. But it's not a major issue.

[AtariDreams]

LLVM changes look unrelated, it was originally copied from OpenBSD it seems. But it's not a major issue.

I did that for consistency. If needed I could split into other PRs

[AtariDreams]

LLVM changes look unrelated, it was originally copied from OpenBSD it seems. But it's not a major issue.

FWIW I opened a few PRs in FreeBSD regarding this.

[jhuber6]

LLVM changes look unrelated, it was originally copied from OpenBSD it seems. But it's not a major issue.

FWIW I opened a few PRs in FreeBSD regarding this.

Yeah, go ahead and move that portion there so the people who know more about LLVM's regex can look at it compared to the libc team.

[AtariDreams]

@jhuber6 Oh you meant the formatting. clang-format did that for some reason. I did not edit the body at all.

[AtariDreams]

@jhuber6 Alright I removed the llvm/Support changes for the sake of the PR

[jhuber6]

Thanks.

[AtariDreams]

Ready!