Add strlcpy implementation (#2395)

2 files changed, 29 insertions, 0 deletions

diff --git a/src/include/ndpi_api.h b/src/include/ndpi_api.h
index acc01fb0f..ca1855532 100644
--- a/src/include/ndpi_api.h
+++ b/src/include/ndpi_api.h
@@ -2245,6 +2245,18 @@ extern "C" {
   void* ndpi_memmem(const void* haystack, size_t haystack_len, const void* needle,
                     size_t needle_len);
 
+  /**
+   * Copies up to -dst_len - 1- characters from -src- to -dst-, ensuring the result is
+   * null-terminated. Measures -src- length and handles potential null pointers.
+   * 
+   * @par dst       = destination buffer
+   * @par src       = source string
+   * @par dst_len   = size of the destination buffer, includes the null terminator
+   * 
+   * @return Length of `src`. If greater or equal to -dst_len-, -dst- has been truncated.
+   */
+  size_t ndpi_strlcpy(char* dst, const char* src, size_t dst_len);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/lib/ndpi_main.c b/src/lib/ndpi_main.c
index ec848a0d2..815aa2e1c 100644
--- a/src/lib/ndpi_main.c
+++ b/src/lib/ndpi_main.c
@@ -11504,3 +11504,20 @@ void* ndpi_memmem(const void* haystack, size_t haystack_len, const void* needle,
 
   return NULL;
 }
+
+size_t ndpi_strlcpy(char *dst, const char* src, size_t dst_len)
+{
+  if (!dst || !src) {
+    return 0;
+  }
+
+  size_t src_len = strlen(src);
+
+  if (dst_len != 0) {
+    size_t len = (src_len < dst_len - 1) ? src_len : dst_len - 1;
+    memcpy(dst, src, len);
+    dst[len] = '\0';
+  }
+
+  return src_len;
+}