diff options
Diffstat (limited to 'src/string')
| -rw-r--r-- | src/string/memccpy.c | 72 | ||||
| -rw-r--r-- | src/string/memcpy.c | 54 | ||||
| -rw-r--r-- | src/string/memmove.c | 60 | ||||
| -rw-r--r-- | src/string/memset.c | 38 | ||||
| -rw-r--r-- | src/string/strcat.c | 61 | ||||
| -rw-r--r-- | src/string/strcpy.c | 219 | ||||
| -rw-r--r-- | src/string/strdup.c | 79 | ||||
| -rw-r--r-- | src/string/strmove.c | 223 |
8 files changed, 806 insertions, 0 deletions
diff --git a/src/string/memccpy.c b/src/string/memccpy.c new file mode 100644 index 0000000..85378d9 --- /dev/null +++ b/src/string/memccpy.c @@ -0,0 +1,72 @@ +/** + * 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, + * but stop if a specific byte is encountered. + * + * @param whither The destination memory segment. + * @param whence The source memory segment. + * @param c The byte to stop at if encountered. + * @param size The maximum number of bytes to copy. + * @return `NULL` if `c` was not encountered, otherwise + * the possition 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 character. + */ +void* memccpy(void* restrict whither, const void* restrict whence, int c, size_t size) +{ + char_t* stop = memchr(whence, c, size); + void* r = NULL + if (stop != NULL) + size = (size_t)(stop - whence), r = whither + size; + memcpy(whither, whence, size); + return r; +} + + +/** + * Copy a memory segment to another, possibly overlapping, segment, + * but stop if a specific byte is encountered. + * + * This is a slibc extension added for completeness. + * + * @param whither The destination memory segment. + * @param whence The source memory segment. + * @param c The byte to stop at if encountered. + * @param size The maximum number of bytes to copy. + * @return `NULL` if `c` was not encountered, otherwise + * the possition 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 character. + */ +void* memcmove(void* whither, const void* whence, int c, size_t size) +{ + char_t* stop = memchr(whence, c, size); + void* r = NULL + if (stop != NULL) + size = (size_t)(stop - whence), r = whither + size; + memmove(whither, whence, size); + return r; +} + diff --git a/src/string/memcpy.c b/src/string/memcpy.c new file mode 100644 index 0000000..4582544 --- /dev/null +++ b/src/string/memcpy.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. + * + * @param whither The destination memory segment. + * @param whence The source memory segment. + * @param size The number of bytes to copy. + * @return `whither` is returned. + */ +void* memcpy(void* restrict whither, const void* restrict whence, size_t size) +{ + /* TODO improve implementation of memcpy */ + void* r = whither; + while (size--) + *whither++ = *whence++; + return r; +} + + +/** + * Copy a memory segment to another, non-overlapping, segment. + * + * This is a GNU extension. + * + * @param whither The destination memory segment. + * @param whence The source memory segment. + * @param size The number of bytes to copy. + * @return `whither + size` is returned. + */ +void* mempcpy(void* restrict whither, const void* restrict whence, size_t size) +{ + return (char*)memcpy(whither, whence, size) + size; +} + diff --git a/src/string/memmove.c b/src/string/memmove.c new file mode 100644 index 0000000..c721609 --- /dev/null +++ b/src/string/memmove.c @@ -0,0 +1,60 @@ +/** + * 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. + * + * @param whither The destination memory segment. + * @param whence The source memory segment. + * @param size The number of bytes to copy. + * @return `whither` is returned. + */ +void* memmove(void* whither, const void* whence, size_t size) +{ + /* TODO improve implementation of memcpy */ + char* d = whither; + const char* s = whence; + if ((size_t)(d - s) < size) + while (size--) + d[size] = s[size]; + else + while (size--) + *d++ = *s++; + return whither; +} + + +/** + * Copy a memory segment to another, possibly overlapping, segment. + * + * 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 size The number of bytes to copy. + * @return `whither + size` is returned. + */ +void* mempmove(void* whither, const void* whence, size_t size) +{ + return (char*)memmove(whither, whence, size) + size; +} + diff --git a/src/string/memset.c b/src/string/memset.c new file mode 100644 index 0000000..c0b87a3 --- /dev/null +++ b/src/string/memset.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> + + + +/** + * Override a memory segment with a repeated character. + * + * @param segment The beginning of the memory segment. + * @param c The character (8 bits wide.) + * @param size The size of the memory segment. + * @return `segment` is returned. + */ +void* memset(void* segment, int c, size_t size) +{ + /* TODO improve implementation of memset */ + char* s = segment; + while (size--) + *s++ = c; + return segment; +} + diff --git a/src/string/strcat.c b/src/string/strcat.c new file mode 100644 index 0000000..4fff095 --- /dev/null +++ b/src/string/strcat.c @@ -0,0 +1,61 @@ +/** + * 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 <stddef.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 bad idea. + * + * @param whither The string to extend. + * @param whence The string to append. + * @return `whither` is returned. + */ +char* strcat(char* restrict whither, const char* restrict whence) +{ + strcpy(whither + strlen(whither), whence); + return whither; +} + + +/** + * 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, laxmen); + return whither; +} + diff --git a/src/string/strcpy.c b/src/string/strcpy.c new file mode 100644 index 0000000..dfbdc75 --- /dev/null +++ b/src/string/strcpy.c @@ -0,0 +1,219 @@ +/** + * 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 <stddef.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. + * @return `whither` is returned. + */ +char* strcpy(char* restrict whither, const char* restrict whence) +{ + return memcpy(whither, whence, strlen(whence) + 1); +} + + +/** + * 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. + * @return `whither + strlen(whence)` is returned. + */ +char* stpcpy(char* restrict whither, const char* restrict whence) +{ + return mempcpy(whither, whence, strlen(whence) + 1) - 1; +} + + +/** + * 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. + * + * @param whither The destination memory segment. + * @param whence The source memory segment. + * @param c The stop byte. + * @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* strccpy(char* restrict whither, const char* restrict whence, int c) +{ + char* r = memccpy(whither, whence, c, strlen(whence) + 1); + if (r) + *r = 0; + return r; +} + + +/** + * 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. + * + * @param whither The destination memory segment. + * @param whence The source memory segment. + * @param str The substring, ignored if `NULL`. + * @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* strstrcpy(char* restrict whither, const char* restrict whence, const char* restrict str) +{ + const char* stop = str == NULL ? NULL : strstr(whence, str); + size_t n = stop == NULL ? strlen(whence) : (size_t)(stop - whence); + char* r = stop == NULL ? NULL ? whither + n; + memcpy(whither, whence, n); + whither[n] = 0; + return r; +} + + +/** + * 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; +} + + +/** + * 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; +} + + +/** + * 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; +} + + +/** + * 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/strdup.c b/src/string/strdup.c new file mode 100644 index 0000000..27783b9 --- /dev/null +++ b/src/string/strdup.c @@ -0,0 +1,79 @@ +/** + * 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 <stddef.h> + + + +/** + * Duplicate a string. + * + * @param string The string to duplicate. + * @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* strdup(const char* string) +{ + size_t n = strlen(string) + 1; + char* r = malloc(n * sizeof(char)); + return r == NULL ? NULL : memcpy(r, string, n); +} + + +/** + * 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); +} + + +/** + * Duplicate a memory segment. + * + * This is a slibc extension. + * + * @param segment The memory segment to duplicate. + * @param size The size of the memory segment. + * @return The new segment. `NULL` is returned on error + * and `errno` is set to indicate the error. + * + * @throws ENOMEM The process could not allocate sufficient amount of memory. + */ +void* memdup(const void* segment, size_t size) +{ + wchar_t* r = malloc(size * sizeof(wchar_t)); + return r == NULL ? NULL : memcpy(r, segment, size); +} + diff --git a/src/string/strmove.c b/src/string/strmove.c new file mode 100644 index 0000000..86298cf --- /dev/null +++ b/src/string/strmove.c @@ -0,0 +1,223 @@ +/** + * 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 <stddef.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. + * @return `whither` is returned. + */ +char* strmove(char* whither, const char* whence) +{ + return memmove(whither, whence, strlen(whence) + 1); +} + + +/** + * 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. + * @return `whither + strlen(whence)` is returned. + */ +char* stpmove(char* whither, const char* whence) +{ + return mempmove(whither, whence, strlen(whence) + 1) - 1; +} + + +/** + * 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. + * + * @param whither The destination memory segment. + * @param whence The source memory segment. + * @param c The stop byte. + * @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* strcmove(char* whither, const char* whence, int c) +{ + char* r = memcmove(whither, whence, c, strlen(whence) + 1); + if (r) + *r = 0; + return r; +} + + +/** + * 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. + * + * @param whither The destination memory segment. + * @param whence The source memory segment. + * @param str The substring, ignored if `NULL`. + * @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* strstrmove(char* whither, const char* whence, const char* restrict str) +{ + const char* stop = str == NULL ? NULL : strstr(whence, str); + size_t n = stop == NULL ? strlen(whence) : (size_t)(stop - whence); + char* r = stop == NULL ? NULL ? whither + n; + memmove(whither, whence, n); + whither[n] = 0; + return r; +} + + +/** + * Copy a memory segment to another, possibly 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* 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; +} + + +/** + * 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; +} + + +/** + * 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; +} + + +/** + * 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; +} + |