1 files changed, 72 insertions, 0 deletions
diff --git a/src/filename_expand.cxx b/src/filename_expand.cxx
new file mode 100644
index 000000000..27e593389
--- /dev/null
+++ b/src/filename_expand.cxx
@@ -0,0 +1,72 @@
+/* expand a file name by substuting environment variables and
+   home directories.  Returns true if any changes were made.
+   to & from may be the same buffer.
+*/
+
+#include <FL/filename.H>
+#include <stdlib.h>
+#include <string.h>
+#ifdef WIN32
+#else
+# include <unistd.h>
+# include <pwd.h>
+#endif
+
+#if defined(WIN32) || defined(__EMX__)
+static inline int isdirsep(char c) {return c=='/' || c=='\\';}
+#else
+#define isdirsep(c) ((c)=='/')
+#endif
+
+int filename_expand(char *to,const char *from) {
+
+  char temp[FL_PATH_MAX];
+  strcpy(temp,from);
+  const char *start = temp;
+  const char *end = temp+strlen(temp);
+
+  int ret = 0;
+
+  for (char *a=temp; a<end; ) {	// for each slash component
+    char *e; for (e=a; e<end && !isdirsep(*e); e++); // find next slash
+    const char *value = 0; // this will point at substitute value
+    switch (*a) {
+    case '~':	// a home directory name
+      if (e <= a+1) {	// current user's directory
+	value = getenv("HOME");
+#ifndef WIN32
+      } else {	// another user's directory
+	struct passwd *pwd;
+	char t = *e; *(char *)e = 0; 
+        pwd = getpwnam(a+1); 
+        *(char *)e = t;
+	    if (pwd) value = pwd->pw_dir;
+#endif
+      }
+      break;
+    case '$':		/* an environment variable */
+      {char t = *e; *(char *)e = 0; value = getenv(a+1); *(char *)e = t;}
+      break;
+    }
+    if (value) {
+      // substitutions that start with slash delete everything before them:
+      if (isdirsep(value[0])) start = a;
+#if defined(WIN32) || defined(__EMX__)
+      // also if it starts with "A:"
+      if (value[0] && value[1]==':') start = a;
+#endif
+      int t = strlen(value); if (isdirsep(value[t-1])) t--;
+      memmove(a+t, e, end+1-e);
+      end = a+t+(end-e);
+      memcpy(a, value, t);
+      ret++;
+    } else {
+      a = e+1;
+#if defined(WIN32) || defined(__EMX__)
+      if (*e == '\\') {*e = '/'; ret++;} // ha ha!
+#endif
+    }
+  }
+  strcpy(to,start);
+  return ret;
+}