Add some BLI helpers needed by asset branch.

`BLI_strncpy_ensure_pad()` is also useful with current master code.

The two others (`BLI_strcmp_ignore_pad()` and `BLI_filelist_duplicate()`)
are only used in asset branch currently, but think they could be useful
in other places too, and simplifies handling of asset branch & future patch review.

Reviewers: campbellbarton

Reviewed By: campbellbarton

Differential Revision: https://developer.blender.org/D965

4 files changed, 133 insertions, 1 deletions

diff --git a/source/blender/blenlib/BLI_fileops.h b/source/blender/blenlib/BLI_fileops.h
index 4f451a6c741..8e056651f7f 100644
--- a/source/blender/blenlib/BLI_fileops.h
+++ b/source/blender/blenlib/BLI_fileops.h
@@ -89,6 +89,9 @@ double BLI_dir_free_space(const char *dir);
 char  *BLI_current_working_dir(char *dir, const size_t maxlen);
 
 unsigned int BLI_dir_contents(const char *dir, struct direntry **filelist);
+void BLI_filelist_duplicate(
+        struct direntry **dest_filelist, struct direntry *src_filelist, unsigned int nrentries,
+        void *(*dup_poin)(void *));
 void BLI_free_filelist(struct direntry *filelist, unsigned int nrentries);
 
 /* Files */
diff --git a/source/blender/blenlib/BLI_string.h b/source/blender/blenlib/BLI_string.h
index b249bc720c6..a390b419c18 100644
--- a/source/blender/blenlib/BLI_string.h
+++ b/source/blender/blenlib/BLI_string.h
@@ -48,6 +48,8 @@ char *BLI_strdupcat(const char *__restrict str1, const char *__restrict str2) AT
 
 char *BLI_strncpy(char *__restrict dst, const char *__restrict src, const size_t maxncpy) ATTR_NONNULL();
 
+char *BLI_strncpy_ensure_pad(char *dst, const char *src, const char pad, size_t maxncpy) ATTR_NONNULL();
+
 size_t BLI_strncpy_rlen(char *__restrict dst, const char *__restrict src, const size_t maxncpy) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
 
 size_t BLI_strcpy_rlen(char *__restrict dst, const char *__restrict src) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
@@ -71,6 +73,8 @@ char *BLI_strcasestr(const char *s, const char *find) ATTR_WARN_UNUSED_RESULT AT
 int BLI_strcasecmp(const char *s1, const char *s2) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
 int BLI_strncasecmp(const char *s1, const char *s2, size_t len) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
 int BLI_natstrcmp(const char *s1, const char *s2) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
+int BLI_strcmp_ignore_pad(const char *str1, const char *str2, const char pad) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
+
 size_t BLI_strnlen(const char *str, const size_t maxlen) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
 void BLI_timestr(double _time, char *str, size_t maxlen) ATTR_NONNULL();
 
diff --git a/source/blender/blenlib/intern/storage.c b/source/blender/blenlib/intern/storage.c
index c062d62bca5..78057b1655f 100644
--- a/source/blender/blenlib/intern/storage.c
+++ b/source/blender/blenlib/intern/storage.c
@@ -409,7 +409,40 @@ unsigned int BLI_dir_contents(const char *dirname,  struct direntry **filelist)
 	return dir_ctx.nrfiles;
 }
 
-/* frees storage for an array of direntries, including the array itself. */
+/**
+ * Deep-duplicate of an array of direntries, including the array itself.
+ *
+ * \param dup_poin If given, called for each non-NULL direntry->poin. Otherwise, pointer is always simply copied over.
+ */
+void BLI_filelist_duplicate(
+        struct direntry **dest_filelist, struct direntry *src_filelist, unsigned int nrentries,
+        void *(*dup_poin)(void *))
+{
+	unsigned int i;
+
+	*dest_filelist = malloc(sizeof(**dest_filelist) * (size_t)(nrentries));
+	for (i = 0; i < nrentries; ++i) {
+		struct direntry * const src = &src_filelist[i];
+		struct direntry *dest = &(*dest_filelist)[i];
+		*dest = *src;
+		if (dest->image) {
+			dest->image = IMB_dupImBuf(src->image);
+		}
+		if (dest->relname) {
+			dest->relname = MEM_dupallocN(src->relname);
+		}
+		if (dest->path) {
+			dest->path = MEM_dupallocN(src->path);
+		}
+		if (dest->poin && dup_poin) {
+			dest->poin = dup_poin(src->poin);
+		}
+	}
+}
+
+/**
+ * frees storage for an array of direntries, including the array itself.
+ */
 void BLI_free_filelist(struct direntry *filelist, unsigned int nrentries)
 {
 	unsigned int i;
diff --git a/source/blender/blenlib/intern/string.c b/source/blender/blenlib/intern/string.c
index eeafc1a9e8f..765e2ea127b 100644
--- a/source/blender/blenlib/intern/string.c
+++ b/source/blender/blenlib/intern/string.c
@@ -126,6 +126,54 @@ char *BLI_strncpy(char *__restrict dst, const char *__restrict src, const size_t
 }
 
 /**
+ * Like BLI_strncpy but ensures dst is always padded by given char, on both sides (unless src is empty).
+ *
+ * \param dst Destination for copy
+ * \param src Source string to copy
+ * \param pad the char to use for padding
+ * \param maxncpy Maximum number of characters to copy (generally the size of dst)
+ * \retval Returns dst
+ */
+char *BLI_strncpy_ensure_pad(char *__restrict dst, const char *__restrict src, const char pad, size_t maxncpy)
+{
+	BLI_assert(maxncpy != 0);
+
+#ifdef DEBUG_STRSIZE
+	memset(dst, 0xff, sizeof(*dst) * maxncpy);
+#endif
+
+	if (src[0] == '\0') {
+		dst[0] = '\0';
+	}
+	else {
+		/* Add heading/trailing wildcards if needed. */
+		size_t idx = 0;
+		size_t srclen;
+
+		if (src[idx] != pad) {
+			dst[idx++] = pad;
+			maxncpy--;
+		}
+		maxncpy--;  /* trailing '\0' */
+
+		srclen = BLI_strnlen(src, maxncpy);
+		if ((src[srclen - 1] != pad) && (srclen == maxncpy)) {
+			srclen--;
+		}
+
+		memcpy(&dst[idx], src, srclen);
+		idx += srclen;
+
+		if (dst[idx - 1] != pad) {
+			dst[idx++] = pad;
+		}
+		dst[idx] = '\0';
+	}
+
+	return dst;
+}
+
+/**
  * Like strncpy but ensures dst is always
  * '\0' terminated.
  *
@@ -566,6 +614,50 @@ int BLI_natstrcmp(const char *s1, const char *s2)
 	return strcmp(s1, s2);
 }
 
+/**
+ * Like strcmp, but will ignore any heading/trailing pad char for comparison.
+ * So e.g. if pad is '*', '*world' and 'world*' will compare equal.
+ */
+int BLI_strcmp_ignore_pad(const char *str1, const char *str2, const char pad)
+{
+	size_t str1_len, str2_len;
+
+	while (*str1 == pad) {
+		str1++;
+	}
+	while (*str2 == pad) {
+		str2++;
+	}
+
+	str1_len = strlen(str1);
+	str2_len = strlen(str2);
+
+	while (str1_len && (str1[str1_len - 1] == pad)) {
+		str1_len--;
+	}
+	while (str2_len && (str2[str2_len - 1] == pad)) {
+		str2_len--;
+	}
+
+	if (str1_len == str2_len) {
+		return strncmp(str1, str2, str2_len);
+	}
+	else if (str1_len > str2_len) {
+		int ret = strncmp(str1, str2, str2_len);
+		if (ret == 0) {
+			ret = 1;
+		}
+		return ret;
+	}
+	else {
+		int ret = strncmp(str1, str2, str1_len);
+		if (ret == 0) {
+			ret = -1;
+		}
+		return ret;
+	}
+}
+
 void BLI_timestr(double _time, char *str, size_t maxlen)
 {
 	/* format 00:00:00.00 (hr:min:sec) string has to be 12 long */