Search for scripts relative to the executable on all(?) platforms

Add a helper to hide the platform-dependent method to get a
canonical, absolute, /-separated path to the executable.

Use this and the relative path from BINDIR to PKGDATADIR to
construct a search path that finds the scripts even if the
installation dir is moved, as long as the structure below $prefix
is maintained.

This method should fully support all the tricks you can to with
autotools to customize the installed layout such as overriding the
default directories at configure-time and overriding the configured
directories at build-time.

The exe path detection methods are combined from
http://openocd.zylin.com/3388 by Rick Foos and
http://openocd.zylin.com/3537 by Steven Stallion, as well as tips
found all over internet.

Change-Id: Ifc9cc9dd0bf52fbd67b1b0f2383318cda0c422c4
Signed-off-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>
Signed-off-by: Steven Stallion <sstallion@gmail.com>
Reviewed-on: http://openocd.zylin.com/3889
Tested-by: jenkins
Reviewed-by: Rick Foos <rfoos@solengtech.com>
Reviewed-by: Paul Fertser <fercerpav@gmail.com>

diff --git a/configure.ac b/configure.ac
index 5630b11169737030126e06bc8c29794e3a04c320..687e95ce9a11c767142c92ff192ca045021bb8b1 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -57,6 +57,7 @@ AC_CHECK_HEADERS([sys/ioctl.h])
 AC_CHECK_HEADERS([sys/param.h])
 AC_CHECK_HEADERS([sys/select.h])
 AC_CHECK_HEADERS([sys/stat.h])
+AC_CHECK_HEADERS([sys/sysctl.h])
 AC_CHECK_HEADERS([sys/time.h])
 AC_CHECK_HEADERS([sys/types.h])
 AC_CHECK_HEADERS([unistd.h])
@@ -86,6 +87,7 @@ AC_CHECK_FUNCS([strnlen])
 AC_CHECK_FUNCS([gettimeofday])
 AC_CHECK_FUNCS([usleep])
 AC_CHECK_FUNCS([vasprintf])
+AC_CHECK_FUNCS([realpath])
 
 # guess-rev.sh only exists in the repository, not in the released archives
 AC_MSG_CHECKING([whether to build a release])

diff --git a/src/helper/options.c b/src/helper/options.c
index b7db10f92e47131a802c20314a5335e5ceedddc8..409abeebb4ab4e37ad031aa69c811b9ab82da29b 100644 (file)
--- a/src/helper/options.c
+++ b/src/helper/options.c
@@ -29,6 +29,15 @@
 
 #include <getopt.h>
 
+#include <limits.h>
+#include <stdlib.h>
+#if IS_DARWIN
+#include <libproc.h>
+#endif
+#ifdef HAVE_SYS_SYSCTL_H
+#include <sys/sysctl.h>
+#endif
+
 static int help_flag, version_flag;
 
 static const struct option long_options[] = {
@@ -50,52 +59,129 @@ int configuration_output_handler(struct command_context *context, const char *li
        return ERROR_OK;
 }
 
-#ifdef _WIN32
-static char *find_suffix(const char *text, const char *suffix)
+/* Return the canonical path to the directory the openocd executable is in.
+ * The path should be absolute, use / as path separator and have all symlinks
+ * resolved. The returned string is malloc'd. */
+static char *find_exe_path(void)
 {
-       size_t text_len = strlen(text);
-       size_t suffix_len = strlen(suffix);
+       char *exepath = NULL;
+
+       do {
+#if IS_WIN32 && !IS_CYGWIN
+               exepath = malloc(MAX_PATH);
+               if (exepath == NULL)
+                       break;
+               GetModuleFileName(NULL, exepath, MAX_PATH);
 
-       if (suffix_len == 0)
-               return (char *)text + text_len;
+               /* Convert path separators to UNIX style, should work on Windows also. */
+               for (char *p = exepath; *p; p++) {
+                       if (*p == '\\')
+                               *p = '/';
+               }
 
-       if (suffix_len > text_len || strncmp(text + text_len - suffix_len, suffix, suffix_len) != 0)
-               return NULL; /* Not a suffix of text */
+#elif IS_DARWIN
+               exepath = malloc(PROC_PIDPATHINFO_MAXSIZE);
+               if (exepath == NULL)
+                       break;
+               if (proc_pidpath(getpid(), exepath, PROC_PIDPATHINFO_MAXSIZE) <= 0) {
+                       free(exepath);
+                       exepath = NULL;
+               }
 
-       return (char *)text + text_len - suffix_len;
-}
+#elif defined(CTL_KERN) && defined(KERN_PROC) && defined(KERN_PROC_PATHNAME) /* *BSD */
+#ifndef PATH_MAX
+#define PATH_MAX 1024
 #endif
+               char *path = malloc(PATH_MAX);
+               if (path == NULL)
+                       break;
+               int mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 };
+               size_t size = PATH_MAX;
 
-static void add_default_dirs(void)
-{
-       const char *run_prefix;
-       char *path;
+               if (sysctl(mib, (u_int)ARRAY_SIZE(mib), path, &size, NULL, 0) != 0)
+                       break;
 
-#ifdef _WIN32
-       char strExePath[MAX_PATH];
-       GetModuleFileName(NULL, strExePath, MAX_PATH);
+#ifdef HAVE_REALPATH
+               exepath = realpath(path, NULL);
+               free(path);
+#else
+               exepath = path;
+#endif
 
-       /* Strip executable file name, leaving path */
-       *strrchr(strExePath, '\\') = '\0';
+#elif defined(HAVE_REALPATH) /* Assume POSIX.1-2008 */
+               /* Try Unices in order of likelihood. */
+               exepath = realpath("/proc/self/exe", NULL); /* Linux/Cygwin */
+               if (exepath == NULL)
+                       exepath = realpath("/proc/self/path/a.out", NULL); /* Solaris */
+               if (exepath == NULL)
+                       exepath = realpath("/proc/curproc/file", NULL); /* FreeBSD (Should be covered above) */
+#endif
+       } while (0);
+
+       if (exepath != NULL) {
+               /* Strip executable file name, leaving path */
+               *strrchr(exepath, '/') = '\0';
+       } else {
+               LOG_WARNING("Could not determine executable path, using configured BINDIR.");
+               LOG_DEBUG("BINDIR = %s", BINDIR);
+#ifdef HAVE_REALPATH
+               exepath = realpath(BINDIR, NULL);
+#else
+               exepath = strdup(BINDIR);
+#endif
+       }
+
+       return exepath;
+}
 
-       /* Convert path separators to UNIX style, should work on Windows also. */
-       for (char *p = strExePath; *p; p++) {
-               if (*p == '\\')
-                       *p = '/';
+static char *find_relative_path(const char *from, const char *to)
+{
+       size_t i;
+
+       /* Skip common /-separated parts of from and to */
+       i = 0;
+       for (size_t n = 0; from[n] == to[n]; n++) {
+               if (from[n] == '\0') {
+                       i = n;
+                       break;
+               }
+               if (from[n] == '/')
+                       i = n + 1;
+       }
+       from += i;
+       to += i;
+
+       /* Count number of /-separated non-empty parts of from */
+       i = 0;
+       while (from[0] != '\0') {
+               if (from[0] != '/')
+                       i++;
+               char *next = strchr(from, '/');
+               if (next == NULL)
+                       break;
+               from = next + 1;
        }
 
-       char *end_of_prefix = find_suffix(strExePath, BINDIR);
-       if (end_of_prefix != NULL)
-               *end_of_prefix = '\0';
+       /* Prepend that number of ../ in front of to */
+       char *relpath = malloc(i * 3 + strlen(to) + 1);
+       relpath[0] = '\0';
+       for (size_t n = 0; n < i; n++)
+               strcat(relpath, "../");
+       strcat(relpath, to);
 
-       run_prefix = strExePath;
-#else
-       run_prefix = "";
-#endif
+       return relpath;
+}
+
+static void add_default_dirs(void)
+{
+       char *path;
+       char *exepath = find_exe_path();
+       char *bin2data = find_relative_path(BINDIR, PKGDATADIR);
 
        LOG_DEBUG("bindir=%s", BINDIR);
        LOG_DEBUG("pkgdatadir=%s", PKGDATADIR);
-       LOG_DEBUG("run_prefix=%s", run_prefix);
+       LOG_DEBUG("exepath=%s", exepath);
+       LOG_DEBUG("bin2data=%s", bin2data);
 
        /*
         * The directory containing OpenOCD-supplied scripts should be
@@ -129,17 +215,20 @@ static void add_default_dirs(void)
        }
 #endif
 
-       path = alloc_printf("%s%s%s", run_prefix, PKGDATADIR, "/site");
+       path = alloc_printf("%s/%s/%s", exepath, bin2data, "site");
        if (path) {
                add_script_search_dir(path);
                free(path);
        }
 
-       path = alloc_printf("%s%s%s", run_prefix, PKGDATADIR, "/scripts");
+       path = alloc_printf("%s/%s/%s", exepath, bin2data, "scripts");
        if (path) {
                add_script_search_dir(path);
                free(path);
        }
+
+       free(exepath);
+       free(bin2data);
 }
 
 int parse_cmdline_args(struct command_context *cmd_ctx, int argc, char *argv[])