helpers: add a function to find an executable in $PATH

Origin commit data
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Branch: ni/coolstream
Commit: e37e425674
Author: Stefan Seyfried <seife@tuxbox-git.slipkontur.de>
Date: 2014-01-26 (Sun, 26 Jan 2014)


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No further description and justification available within origin commit message!

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This commit was generated by Migit

src/system/helpers.cpp

@@ -290,6 +290,35 @@ bool get_mem_usage(unsigned long &kbtotal, unsigned long &kbfree)
 	return true;
 }
 
+std::string find_executable(const char *name)
+{
+	struct stat s;
+	char *path = getenv("PATH");
+	char *p, *n;
+	if (! path)
+		path = strdupa("/bin:/usr/bin:/sbin:/usr/sbin");
+	if (name[0] == '/') { /* full path given */
+		if (!access(name, X_OK) && !stat(name, &s) && S_ISREG(s.st_mode))
+			return std::string(name);
+		return "";
+	}
+
+	p = path;
+	while (p) {
+		n = strchr(p, ':');
+		if (n)
+			*n++ = '\0';
+		if (*p != '\0') {
+			std::string tmp = std::string(p) + "/" + std::string(name);
+			const char *f = tmp.c_str();
+			if (!access(f, X_OK) && !stat(f, &s) && S_ISREG(s.st_mode))
+				return tmp;
+		}
+		p = n;
+	}
+	return "";
+}
+
 std::string _getPathName(std::string &path, std::string sep)
 {
 	size_t pos = path.find_last_of(sep);

src/system/helpers.h

@@ -41,6 +41,8 @@ bool get_fs_usage(const char * dir, uint64_t &btotal, uint64_t &bused, long *bsi
 bool get_mem_usage(unsigned long &total, unsigned long &free);
 void mySleep(int sec);
 
+std::string find_executable(const char *name);
+
 std::string getPathName(std::string &path);
 std::string getBaseName(std::string &path);
 std::string getFileName(std::string &file);