split out string/strn/ from string/str/

Signed-off-by: Mattias Andrée <maandree@operamail.com>

15 files changed, 686 insertions, 0 deletions

diff --git a/src/string/strn/stpncpy.c b/src/string/strn/stpncpy.c
new file mode 100644
index 0000000..876eaf0
--- /dev/null
+++ b/src/string/strn/stpncpy.c
@@ -0,0 +1,46 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Copy a memory segment to another, non-overlapping, segment,
+ * stop when a NUL byte is encountered.
+ * 
+ * This is a GNU extension.
+ * 
+ * @param   whither  The destination memory segment.
+ * @param   whence   The source memory segment.
+ * @param   maxlen   The maximum number of bytes to copy.
+ *                   NOTE that if the resulting string at least this
+ *                   long, no NUL byte will be written to `whither'.
+ *                   On the otherhand, if the resultnig string is
+ *                   shorter, `whither` will be filled with NUL bytes
+ *                   until this amount of bytes have been written.
+ * @return           `whither` plus the number of written bytes,
+ *                   excluding NUL bytes, is returned.
+ */
+char* stpncpy(char* restrict whither, const char* restrict whence, size_t maxlen)
+{
+  size_t n = strnlen(whence, maxlen);
+  memcpy(whither, whence, n);
+  memset(whither, 0, maxlen - n);
+  return whither + n;
+}
+
diff --git a/src/string/strn/stpnmove.c b/src/string/strn/stpnmove.c
new file mode 100644
index 0000000..a0a0de9
--- /dev/null
+++ b/src/string/strn/stpnmove.c
@@ -0,0 +1,47 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Copy a memory segment to another, possibly overlapping, segment,
+ * stop when a NUL byte is encountered.
+ * 
+ * This is a slibc extension added for completeness.
+ * It is only available if GNU extensions are available.
+ * 
+ * @param   whither  The destination memory segment.
+ * @param   whence   The source memory segment.
+ * @param   maxlen   The maximum number of bytes to copy.
+ *                   NOTE that if the resulting string at least this
+ *                   long, no NUL byte will be written to `whither'.
+ *                   On the otherhand, if the resultnig string is
+ *                   shorter, `whither` will be filled with NUL bytes
+ *                   until this amount of bytes have been written.
+ * @return           `whither` plus the number of written bytes,
+ *                   excluding NUL bytes, is returned.
+ */
+char* stpnmove(char* whither, const char* whence, size_t maxlen)
+{
+  size_t n = strnlen(whence, maxlen);
+  memmove(whither, whence, n);
+  memset(whither, 0, maxlen - n);
+  return whither + n;
+}
+
diff --git a/src/string/strn/strcncpy.c b/src/string/strn/strcncpy.c
new file mode 100644
index 0000000..5036c7d
--- /dev/null
+++ b/src/string/strn/strcncpy.c
@@ -0,0 +1,54 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Copy a memory segment to another, non-overlapping, segment,
+ * stop when a NUL byte or a specified byte is encountered.
+ * 
+ * This is a slibc extension added for completeness.
+ * It is only available if GNU extensions are available.
+ * 
+ * @param   whither  The destination memory segment.
+ * @param   whence   The source memory segment.
+ * @param   c        The stop byte.
+ * @param   maxlen   The maximum number of bytes to copy.
+ *                   NOTE that if the resulting string at least this
+ *                   long, no NUL byte will be written to `whither'.
+ *                   On the otherhand, if the resultnig string is
+ *                   shorter, `whither` will be filled with NUL bytes
+ *                   until this amount of bytes have been written.
+ * @return           `NULL` if `c` was not encountered, otherwise
+ *                   the position of `c` translated to `whither`,
+ *                   that is, the address of `whither` plus the
+ *                   number of copied characters; the address of
+ *                   one character passed the last written non-NUL
+ *                   character.
+ */
+char* strcncpy(char* restrict whither, const char* restrict whence, int c, size_t maxlen)
+{
+  const char* stop = memchr(whence, c, maxlen);
+  size_t n = stop == NULL ? strnlen(whence, maxlen) : (size_t)(stop - whence);
+  char* r = stop == NULL ? NULL : (whither + n);
+  memcpy(whither, whence, n);
+  memset(whither, 0, maxlen - n);
+  return r;
+}
+
diff --git a/src/string/strn/strcnmove.c b/src/string/strn/strcnmove.c
new file mode 100644
index 0000000..f418e92
--- /dev/null
+++ b/src/string/strn/strcnmove.c
@@ -0,0 +1,54 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Copy a memory segment to another, possibly overlapping, segment,
+ * stop when a NUL byte or a specified byte is encountered.
+ * 
+ * This is a slibc extension added for completeness.
+ * It is only available if GNU extensions are available.
+ * 
+ * @param   whither  The destination memory segment.
+ * @param   whence   The source memory segment.
+ * @param   c        The stop byte.
+ * @param   maxlen   The maximum number of bytes to copy.
+ *                   NOTE that if the resulting string at least this
+ *                   long, no NUL byte will be written to `whither'.
+ *                   On the otherhand, if the resultnig string is
+ *                   shorter, `whither` will be filled with NUL bytes
+ *                   until this amount of bytes have been written.
+ * @return           `NULL` if `c` was not encountered, otherwise
+ *                   the position of `c` translated to `whither`,
+ *                   that is, the address of `whither` plus the
+ *                   number of copied characters; the address of
+ *                   one character passed the last written non-NUL
+ *                   character.
+ */
+char* strcnmove(char* whither, const char* whence, int c, size_t maxlen)
+{
+  const char* stop = memchr(whence, c, maxlen);
+  size_t n = stop == NULL ? strnlen(whence, maxlen) : (size_t)(stop - whence);
+  char* r = stop == NULL ? NULL : (whither + n);
+  memmove(whither, whence, n);
+  memset(whither, 0, maxlen - n);
+  return r;
+}
+
diff --git a/src/string/strn/strncasecmp.c b/src/string/strn/strncasecmp.c
new file mode 100644
index 0000000..919ff36
--- /dev/null
+++ b/src/string/strn/strncasecmp.c
@@ -0,0 +1,50 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+#include <ctype.h>
+
+
+
+/**
+ * Compare two strings alphabetically in a case insensitive manner.
+ * Be aware, only ASCII characters are case insensitive, non-ASCII
+ * characters are case sensitive.
+ * 
+ * @param   a       A negative value is returned if this is the lesser.
+ * @param   b       A positive value is returned if this is the lesser.
+ * @param   length  The maximum number of characters to compare.
+ * @return          Zero is returned if `a` and `b` are equal, otherwise,
+ *                  see the specifications for `a` and `b`.
+ */
+int strncasecmp(const char* a, const char* b, size_t length)
+{
+  int c1, c2;
+  for (; length--; a++, b++)
+    if (*a != *b)
+      {
+	c1 = isalpha(*a) ? tolower(*a) : (int)*a;
+	c2 = isalpha(*b) ? tolower(*b) : (int)*b;
+	if ((c1 -= c2))
+	  return c1;
+      }
+    else if (!*a && !*b)  return 0;
+    else if (!*a)         return -1;
+    else if (!*b)         return +1;
+  return 0;
+}
+
diff --git a/src/string/strn/strncasestr.c b/src/string/strn/strncasestr.c
new file mode 100644
index 0000000..e95dc4b
--- /dev/null
+++ b/src/string/strn/strncasestr.c
@@ -0,0 +1,38 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Finds the first occurrence of a substring.
+ * This search is case insensitive.
+ * 
+ * This is a slibc extension added for completeness.
+ * 
+ * @param   haystack  The string to search.
+ * @param   needle    The sought after substring.
+ * @param   maxlen    The maximum number of character to search.
+ * @return            Pointer to the first occurrence of the
+ *                    substring, `NULL` if not found.
+ */
+char* (strncasestr)(const char* haystack, const char* needle, size_t maxlen)
+{
+  return (memcasemem)(haystack, strnlen(haystack, maxlen), needle, strlen(needle));
+}
+
diff --git a/src/string/strn/strncat.c b/src/string/strn/strncat.c
new file mode 100644
index 0000000..e7db0f2
--- /dev/null
+++ b/src/string/strn/strncat.c
@@ -0,0 +1,43 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Concatenate a string to the end of another string.
+ * The resulting strings must not overlap with the appended string.
+ * 
+ * The use of this function is often a really bad idea.
+ * 
+ * @param   whither  The string to extend.
+ * @param   whence   The string to append.
+ * @param   maxlen   The maximum number of bytes to copy.
+ *                   NOTE that if the resulting string at least this
+ *                   long, no NUL byte will be written to `whither'.
+ *                   On the otherhand, if the resultnig string is
+ *                   shorter, `whither` will be filled with NUL bytes
+ *                   until this amount of bytes have been written.
+ * @return           `whither` is returned.
+ */
+char* strncat(char* restrict whither, const char* restrict whence, size_t maxlen)
+{
+  strncpy(whither + strlen(whither), whence, maxlen);
+  return whither;
+}
+
diff --git a/src/string/strn/strncmp.c b/src/string/strn/strncmp.c
new file mode 100644
index 0000000..daf5be5
--- /dev/null
+++ b/src/string/strn/strncmp.c
@@ -0,0 +1,39 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Compare two strings alphabetically in a case sensitive manner.
+ * 
+ * @param   a       A negative value is returned if this is the lesser.
+ * @param   b       A positive value is returned if this is the lesser.
+ * @param   length  The maximum number of characters to compare.
+ * @return          Zero is returned if `a` and `b` are equal, otherwise,
+ *                  see the specifications for `a` and `b`.
+ */
+int strncmp(const char* a, const char* b, size_t length)
+{
+  size_t n = strnlen(a, length);
+  size_t m = strnlen(b, length);
+  int r = memcmp(a, b, (n < m ? n : m));
+  return r ? r : n == m ? 0 : n < m ? -1 : +1;
+}
+
+
diff --git a/src/string/strn/strncpy.c b/src/string/strn/strncpy.c
new file mode 100644
index 0000000..f3eba84
--- /dev/null
+++ b/src/string/strn/strncpy.c
@@ -0,0 +1,43 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Copy a memory segment to another, non-overlapping, segment,
+ * stop when a NUL byte is encountered.
+ * 
+ * @param   whither  The destination memory segment.
+ * @param   whence   The source memory segment.
+ * @param   maxlen   The maximum number of bytes to copy.
+ *                   NOTE that if the resulting string at least this
+ *                   long, no NUL byte will be written to `whither'.
+ *                   On the otherhand, if the resultnig string is
+ *                   shorter, `whither` will be filled with NUL bytes
+ *                   until this amount of bytes have been written.
+ * @return           `whither` is returned.
+ */
+char* strncpy(char* restrict whither, const char* restrict whence, size_t maxlen)
+{
+  size_t n = strnlen(whence, maxlen);
+  memcpy(whither, whence, n);
+  memset(whither, 0, maxlen - n);
+  return whither;
+}
+
diff --git a/src/string/strn/strndup.c b/src/string/strn/strndup.c
new file mode 100644
index 0000000..ca3b3f0
--- /dev/null
+++ b/src/string/strn/strndup.c
@@ -0,0 +1,43 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+#include <stdlib.h>
+
+
+
+/**
+ * Duplicate a string.
+ * 
+ * This is a GNU extension.
+ * 
+ * @param   string  The string to duplicate.
+ * @param   maxlen  Truncate the string to this length, if it is longer.
+ *                  A NUL byte is guaranteed to always be written
+ *                  upon successful completion.
+ * @return          The new string. `NULL` is returned on error
+ *                  and `errno` is set to indicate the error.
+ * 
+ * @throws  ENOMEM  The process could not allocate sufficient amount of memory.
+ */
+char* strndup(const char* string, size_t maxlen)
+{
+  size_t n = strnlen(string, maxlen) + 1;
+  char* r = malloc(n * sizeof(char));
+  return r == NULL ? NULL : memcpy(r, string, n * sizeof(char));
+}
+
diff --git a/src/string/strn/strnlen.c b/src/string/strn/strnlen.c
new file mode 100644
index 0000000..5473682
--- /dev/null
+++ b/src/string/strn/strnlen.c
@@ -0,0 +1,36 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Variant of `strlen` that only inspects the
+ * beginning of a string.
+ * 
+ * @param   str     The string.
+ * @param   maxlen  The number of bytes to inspect, at most.
+ * @return          The number of bytes before, the first NUL byte.
+ *                  `maxlen` if no NUL byte was found.
+ */
+size_t strnlen(const char* str, size_t maxlen)
+{
+  const char* end = memchr(str, 0, maxlen);
+  return end == NULL ? maxlen : (size_t)(end - str);
+}
+
diff --git a/src/string/strn/strnmove.c b/src/string/strn/strnmove.c
new file mode 100644
index 0000000..a8b3224
--- /dev/null
+++ b/src/string/strn/strnmove.c
@@ -0,0 +1,45 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Copy a memory segment to another, possibly overlapping, segment,
+ * stop when a NUL byte is encountered.
+ * 
+ * This is a slibc extension added for completeness.
+ * 
+ * @param   whither  The destination memory segment.
+ * @param   whence   The source memory segment.
+ * @param   maxlen   The maximum number of bytes to copy.
+ *                   NOTE that if the resulting string at least this
+ *                   long, no NUL byte will be written to `whither'.
+ *                   On the otherhand, if the resultnig string is
+ *                   shorter, `whither` will be filled with NUL bytes
+ *                   until this amount of bytes have been written.
+ * @return           `whither` is returned.
+ */
+char* strnmove(char* whither, const char* whence, size_t maxlen)
+{
+  size_t n = strnlen(whence, maxlen);
+  memmove(whither, whence, n);
+  memset(whither, 0, maxlen - n);
+  return whither;
+}
+
diff --git a/src/string/strn/strnstr.c b/src/string/strn/strnstr.c
new file mode 100644
index 0000000..8db61ac
--- /dev/null
+++ b/src/string/strn/strnstr.c
@@ -0,0 +1,39 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Finds the first occurrence of a substring.
+ * This search is case sensitive.
+ * 
+ * This is a slibc extension added for because it was useful
+ * in implementing slibc itself.
+ * 
+ * @param   haystack  The string to search.
+ * @param   needle    The sought after substring.
+ * @param   maxlen    The maximum number of character to search.
+ * @return            Pointer to the first occurrence of the
+ *                    substring, `NULL` if not found.
+ */
+char* (strnstr)(const char* haystack, const char* needle, size_t maxlen)
+{
+  return (memmem)(haystack, strnlen(haystack, maxlen), needle, strlen(needle));
+}
+
diff --git a/src/string/strn/strstrncpy.c b/src/string/strn/strstrncpy.c
new file mode 100644
index 0000000..0beb8ec
--- /dev/null
+++ b/src/string/strn/strstrncpy.c
@@ -0,0 +1,55 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Copy a memory segment to another, non-overlapping, segment,
+ * stop when a NUL byte or a specified substring is encountered.
+ * 
+ * This is a slibc extension added for completeness.
+ * It is only available if GNU extensions are available.
+ * 
+ * @param   whither  The destination memory segment.
+ * @param   whence   The source memory segment.
+ * @param   str      The substring, ignored if `NULL`.
+ *                   NOTE that if the resulting string at least this
+ *                   long, no NUL byte will be written to `whither'.
+ *                   On the otherhand, if the resultnig string is
+ *                   shorter, `whither` will be filled with NUL bytes
+ *                   until this amount of bytes have been written.
+ * @param   maxlen   The maximum number of bytes to copy.
+ * @return           `NULL` if `str` was not encountered, otherwise
+ *                   the position of `str` translated to `whither`,
+ *                   that is, the address of `whither` plus the
+ *                   number of copied characters; the address of
+ *                   one character passed the last written non-NUL
+ *                   character.
+ */
+char* strstrncpy(char* restrict whither, const char* restrict whence,
+		 const char* restrict str, size_t maxlen)
+{
+  const char* stop = strnstr(whence, str, maxlen);
+  size_t n = stop == NULL ? strnlen(whence, maxlen) : (size_t)(stop - whence);
+  char* r = stop == NULL ? NULL : (whither + n);
+  memcpy(whither, whence, n);
+  memset(whither, 0, maxlen - n);
+  return r;
+}
+
diff --git a/src/string/strn/strstrnmove.c b/src/string/strn/strstrnmove.c
new file mode 100644
index 0000000..9bec614
--- /dev/null
+++ b/src/string/strn/strstrnmove.c
@@ -0,0 +1,54 @@
+/**
+ * slibc — Yet another C library
+ * Copyright © 2015  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <string.h>
+
+
+
+/**
+ * Copy a memory segment to another, possibly overlapping, segment,
+ * stop when a NUL byte or a specified substring is encountered.
+ * 
+ * This is a slibc extension added for completeness.
+ * It is only available if GNU extensions are available.
+ * 
+ * @param   whither  The destination memory segment.
+ * @param   whence   The source memory segment.
+ * @param   str      The substring, ignored if `NULL`.
+ *                   NOTE that if the resulting string at least this
+ *                   long, no NUL byte will be written to `whither'.
+ *                   On the otherhand, if the resultnig string is
+ *                   shorter, `whither` will be filled with NUL bytes
+ *                   until this amount of bytes have been written.
+ * @param   maxlen   The maximum number of bytes to copy.
+ * @return           `NULL` if `str` was not encountered, otherwise
+ *                   the position of `str` translated to `whither`,
+ *                   that is, the address of `whither` plus the
+ *                   number of copied characters; the address of
+ *                   one character passed the last written non-NUL
+ *                   character.
+ */
+char* strstrnmove(char* whither, const char* whence, const char* restrict str, size_t maxlen)
+{
+  const char* stop = strnstr(whence, str, maxlen);
+  size_t n = stop == NULL ? strnlen(whence, maxlen) : (size_t)(stop - whence);
+  char* r = stop == NULL ? NULL : (whither + n);
+  memmove(whither, whence, n);
+  memset(whither, 0, maxlen - n);
+  return r;
+}
+