Merge pull request opencv#8543 from csukuangfj:fix-String

alalek · alalek · commit dcf3d988d565 · 2017-06-28T11:20:29.000Z
diff --git a/modules/core/include/opencv2/core/cvstd.hpp b/modules/core/include/opencv2/core/cvstd.hpp
@@ -489,7 +489,7 @@ class CV_EXPORTS String
 
     static const size_t npos = size_t(-1);
 
-    explicit String();
+    String();
     String(const String& str);
     String(const String& str, size_t pos, size_t len = npos);
     String(const char* s);
@@ -627,13 +627,15 @@ String::String(const char* s, size_t n)
     : cstr_(0), len_(0)
 {
     if (!n) return;
+    if (!s) return;
     memcpy(allocate(n), s, n);
 }
 
 inline
 String::String(size_t n, char c)
     : cstr_(0), len_(0)
 {
+    if (!n) return;
     memset(allocate(n), c, n);
 }
 
@@ -642,6 +644,7 @@ String::String(const char* first, const char* last)
     : cstr_(0), len_(0)
 {
     size_t len = (size_t)(last - first);
+    if (!len) return;
     memcpy(allocate(len), first, len);
 }
 
@@ -650,6 +653,7 @@ String::String(Iterator first, Iterator last)
     : cstr_(0), len_(0)
 {
     size_t len = (size_t)(last - first);
+    if (!len) return;
     char* str = allocate(len);
     while (first != last)
     {

Original file line number	Diff line number	Diff line change
`@@ -489,7 +489,7 @@ class CV_EXPORTS String`
`489`	`489`
`490`	`490`	`static const size_t npos = size_t(-1);`
`491`	`491`
`492`		`- explicit String();`
	`492`	`+ String();`
`493`	`493`	`String(const String& str);`
`494`	`494`	`String(const String& str, size_t pos, size_t len = npos);`
`495`	`495`	`String(const char* s);`
`@@ -627,13 +627,15 @@ String::String(const char* s, size_t n)`
`627`	`627`	`: cstr_(0), len_(0)`
`628`	`628`	`{`
`629`	`629`	`if (!n) return;`
	`630`	`+ if (!s) return;`
`630`	`631`	`memcpy(allocate(n), s, n);`
`631`	`632`	`}`
`632`	`633`
`633`	`634`	`inline`
`634`	`635`	`String::String(size_t n, char c)`
`635`	`636`	`: cstr_(0), len_(0)`
`636`	`637`	`{`
	`638`	`+ if (!n) return;`
`637`	`639`	`memset(allocate(n), c, n);`
`638`	`640`	`}`
`639`	`641`
`@@ -642,6 +644,7 @@ String::String(const char* first, const char* last)`
`642`	`644`	`: cstr_(0), len_(0)`
`643`	`645`	`{`
`644`	`646`	`size_t len = (size_t)(last - first);`
	`647`	`+ if (!len) return;`
`645`	`648`	`memcpy(allocate(len), first, len);`
`646`	`649`	`}`
`647`	`650`
`@@ -650,6 +653,7 @@ String::String(Iterator first, Iterator last)`
`650`	`653`	`: cstr_(0), len_(0)`
`651`	`654`	`{`
`652`	`655`	`size_t len = (size_t)(last - first);`
	`656`	`+ if (!len) return;`
`653`	`657`	`char* str = allocate(len);`
`654`	`658`	`while (first != last)`
`655`	`659`	`{`