From 460ae064c9b460a37e21bb0c028265444e18cb2e Mon Sep 17 00:00:00 2001
From: Pedro <pedroj.sotor@uqvirtual.edu.co>
Date: Thu, 8 Oct 2026 22:31:45 -0500
Subject: [PATCH] feat(libc): implement strsep and memccpy

---
 core/libs/prx/libc/src/StringExtensions.cpp | 24 +++++++++++++++++++++
 core/libs/tests/GuestStrings.cpp            | 17 +++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/core/libs/prx/libc/src/StringExtensions.cpp b/core/libs/prx/libc/src/StringExtensions.cpp
index a9a7597632b..18e9f00f45b 100644
--- a/core/libs/prx/libc/src/StringExtensions.cpp
+++ b/core/libs/prx/libc/src/StringExtensions.cpp
@@ -73,4 +73,28 @@ char* APS5_VABI strtok_nid_postfix(char* text, const char* delimiters) {
     return strtok_r_nid_postfix(text, delimiters, &state);
 }
 
+char* APS5_VABI strsep_nid_postfix(char** stringp, const char* delimiters) {
+    char* token = *stringp;
+    if (token == nullptr) return nullptr;
+    char* end = token + std::strcspn(token, delimiters);
+    if (*end != '\0') {
+        *end = '\0';
+        *stringp = end + 1;
+    } else {
+        *stringp = nullptr;
+    }
+    return token;
+}
+
+void* APS5_VABI memccpy_nid_postfix(void* destination, const void* source, int stop, std::size_t count) {
+    const auto found = static_cast<const unsigned char*>(std::memchr(source, static_cast<unsigned char>(stop), count));
+    if (found == nullptr) {
+        std::memcpy(destination, source, count);
+        return nullptr;
+    }
+    const auto copied = static_cast<std::size_t>(found - static_cast<const unsigned char*>(source)) + 1;
+    std::memcpy(destination, source, copied);
+    return static_cast<unsigned char*>(destination) + copied;
+}
+
 }
diff --git a/core/libs/tests/GuestStrings.cpp b/core/libs/tests/GuestStrings.cpp
index 019e4425c96..cc7cd53bd9e 100644
--- a/core/libs/tests/GuestStrings.cpp
+++ b/core/libs/tests/GuestStrings.cpp
@@ -15,6 +15,8 @@ std::size_t APS5_VABI strcspn_nid_postfix(const char*, const char*);
 std::size_t APS5_VABI strlcat_nid_postfix(char*, const char*, std::size_t);
 char* APS5_VABI strtok_r_nid_postfix(char*, const char*, char**);
 char* APS5_VABI strtok_nid_postfix(char*, const char*);
+char* APS5_VABI strsep_nid_postfix(char**, const char*);
+void* APS5_VABI memccpy_nid_postfix(void*, const void*, int, std::size_t);
 char* APS5_VABI strcasestr_nid_postfix(const char*, const char*);
 int APS5_VABI strcpy_s_nid_postfix(char*, std::size_t, const char*);
 int APS5_VABI strcat_s_nid_postfix(char*, std::size_t, const char*);
@@ -163,5 +165,20 @@ int main() {
     Require(strcasestr_nid_postfix("", "a") == nullptr);
     const char highBytes[] = {static_cast<char>(0xff), 'A', 0};
     Require(strcasestr_nid_postfix(highBytes, "a") == highBytes + 1);
+    char separated[] = "a,,b:c";
+    char* cursor = separated;
+    Require(std::strcmp(strsep_nid_postfix(&cursor, ",:"), "a") == 0);
+    Require(std::strcmp(strsep_nid_postfix(&cursor, ",:"), "") == 0);
+    Require(std::strcmp(strsep_nid_postfix(&cursor, ",:"), "b") == 0);
+    Require(std::strcmp(strsep_nid_postfix(&cursor, ",:"), "c") == 0);
+    Require(cursor == nullptr && strsep_nid_postfix(&cursor, ",") == nullptr);
+    char* nothing = nullptr;
+    Require(strsep_nid_postfix(&nothing, ",") == nullptr);
+    char copy[8] = {};
+    Require(memccpy_nid_postfix(copy, "abcdef", 'c', 6) == copy + 3 && std::memcmp(copy, "abc", 3) == 0);
+    char partial[4] = {};
+    Require(memccpy_nid_postfix(partial, "abcd", 'z', 4) == nullptr && std::memcmp(partial, "abcd", 4) == 0);
+    Require(memccpy_nid_postfix(copy, "xyz", 'x' + 256, 3) == copy + 1);
+    Require(memccpy_nid_postfix(copy, "xyz", 'x', 0) == nullptr);
     return CheckMemcpyOverlap() ? 0 : 1;
 }