str: add an overloaded startswith() utility method

for various string types and use it in a few places.

2 files changed, 34 insertions, 1 deletions

diff --git a/src/base/hostinfo.cc b/src/base/hostinfo.cc
index 857ccfa7f..15413de2a 100644
--- a/src/base/hostinfo.cc
+++ b/src/base/hostinfo.cc
@@ -45,6 +45,7 @@
 #include <string>
 
 #include "base/misc.hh"
+#include "base/str.hh"
 #include "base/types.hh"
 
 using namespace std;
@@ -77,7 +78,7 @@ procInfo(const char *filename, const char *target)
 
     while (fp && !feof(fp) && !done) {
         if (fgets(line, 80, fp)) {
-            if (strncmp(line, target, strlen(target)) == 0) {
+            if (startswith(line, target)) {
                 snprintf(format, sizeof(format), "%s %%ld", target);
                 sscanf(line, format, &usage);
 
diff --git a/src/base/str.hh b/src/base/str.hh
index 6d617df72..b3f3153ec 100644
--- a/src/base/str.hh
+++ b/src/base/str.hh
@@ -33,6 +33,7 @@
 #define __STR_HH__
 
 #include <cctype>
+#include <cstring>
 #include <sstream>
 #include <string>
 #include <vector>
@@ -140,4 +141,35 @@ quote(const std::string &s)
     return ret;
 }
 
+
+/**
+ * Return true if 's' starts with the prefix string 'prefix'.
+ */
+inline bool
+startswith(const char *s, const char *prefix)
+{
+    return (strncmp(s, prefix, strlen(prefix)) == 0);
+}
+
+
+/**
+ * Return true if 's' starts with the prefix string 'prefix'.
+ */
+inline bool
+startswith(const std::string &s, const char *prefix)
+{
+    return (s.compare(0, strlen(prefix), prefix) == 0);
+}
+
+
+/**
+ * Return true if 's' starts with the prefix string 'prefix'.
+ */
+inline bool
+startswith(const std::string &s, const std::string &prefix)
+{
+    return (s.compare(0, prefix.size(), prefix) == 0);
+}
+
+
 #endif //__STR_HH__