Detect appended data to the DP executable.

[xonotic/darkplaces.git] / sys_shared.c

diff --git a/sys_shared.c b/sys_shared.c
index b2a712fcb2bb6ed2eb1903695518ad850d2cd8f2..3b83a49888e5cc2af639b12f90c6522afcff0250 100644 (file)
--- a/sys_shared.c
+++ b/sys_shared.c
@@ -421,3 +421,57 @@ void Sys_Sleep(int microseconds)
                printf("%d %d # debugsleep\n", microseconds, (unsigned int)(t * 1000000));
        }
 }
+
+const char *Sys_FindInPATH(const char *name, char namesep, const char *PATH, char pathsep, char *buf, size_t bufsize)
+{
+       const char *p = PATH;
+       const char *q;
+       if(p && name)
+       {
+               while((q = strchr(p, ':')))
+               {
+                       dpsnprintf(buf, bufsize, "%.*s%c%s", (int)(q-p), p, namesep, name);
+                       if(FS_SysFileExists(buf))
+                               return buf;
+                       p = q + 1;
+               }
+               if(!q) // none found - try the last item
+               {
+                       dpsnprintf(buf, bufsize, "%s%c%s", p, namesep, name);
+                       if(FS_SysFileExists(buf))
+                               return buf;
+               }
+       }
+       return name;
+}
+
+const char *Sys_FindExecutableName(void)
+{
+#if defined(WIN32)
+       return com_argv[0];
+#else
+       static char exenamebuf[MAX_OSPATH+1];
+       ssize_t n = -1;
+#if defined(__FreeBSD__)
+       n = readlink("/proc/curproc/file", exenamebuf, sizeof(exenamebuf)-1);
+#elif defined(__linux__)
+       n = readlink("/proc/self/exe", exenamebuf, sizeof(exenamebuf)-1);
+#endif
+       if(n > 0 && (size_t)(n) < sizeof(exenamebuf))
+       {
+               exenamebuf[n] = 0;
+               return exenamebuf;
+       }
+       if(strchr(com_argv[0], '/'))
+               return com_argv[0]; // possibly a relative path
+       else
+               return Sys_FindInPATH(com_argv[0], '/', getenv("PATH"), ':', exenamebuf, sizeof(exenamebuf));
+#endif
+}
+
+void Sys_ProvideSelfFD(void)
+{
+       if(com_selffd != -1)
+               return;
+       com_selffd = FS_SysOpenFD(Sys_FindExecutableName(), "rb", false);
+}