+
+/* Adjust a relative path name based on the reference path.
+ For example:
+
+ Relative path Reference path Result
+ ------------- -------------- ------
+ bar.o lib.a bar.o
+ foo/bar.o lib.a foo/bar.o
+ bar.o foo/lib.a ../bar.o
+ foo/bar.o baz/lib.a ../foo/bar.o
+ bar.o ../lib.a <parent of current dir>/bar.o
+ ; ../bar.o ../lib.a bar.o
+ ; ../bar.o lib.a ../bar.o
+ foo/bar.o ../lib.a <parent of current dir>/foo/bar.o
+ bar.o ../../lib.a <grandparent>/<parent>/bar.o
+ bar.o foo/baz/lib.a ../../bar.o
+
+ Note - the semicolons above are there to prevent the BFD chew
+ utility from interpreting those lines as prototypes to put into
+ the autogenerated bfd.h header...
+
+ Note - the string is returned in a static buffer. */
+
+static const char *
+adjust_relative_path (const char * path, const char * ref_path)
+{
+ static char *pathbuf = NULL;
+ static unsigned int pathbuf_len = 0;
+ const char *pathp;
+ const char *refp;
+ char * lpath;
+ char * rpath;
+ unsigned int len;
+ unsigned int dir_up = 0;
+ unsigned int dir_down = 0;
+ char *newp;
+ char * pwd = getpwd ();
+ const char * down;
+
+ /* Remove symlinks, '.' and '..' from the paths, if possible. */
+ lpath = lrealpath (path);
+ pathp = lpath == NULL ? path : lpath;
+
+ rpath = lrealpath (ref_path);
+ refp = rpath == NULL ? ref_path : rpath;
+
+ /* Remove common leading path elements. */
+ for (;;)
+ {
+ const char *e1 = pathp;
+ const char *e2 = refp;
+
+ while (*e1 && ! IS_DIR_SEPARATOR (*e1))
+ ++e1;
+ while (*e2 && ! IS_DIR_SEPARATOR (*e2))
+ ++e2;
+ if (*e1 == '\0' || *e2 == '\0' || e1 - pathp != e2 - refp
+ || filename_ncmp (pathp, refp, e1 - pathp) != 0)
+ break;
+ pathp = e1 + 1;
+ refp = e2 + 1;
+ }
+
+ len = strlen (pathp) + 1;
+ /* For each leading path element in the reference path,
+ insert "../" into the path. */
+ for (; *refp; ++refp)
+ if (IS_DIR_SEPARATOR (*refp))
+ {
+ /* PR 12710: If the path element is "../" then instead of
+ inserting "../" we need to insert the name of the directory
+ at the current level. */
+ if (refp > ref_path + 1
+ && refp[-1] == '.'
+ && refp[-2] == '.')
+ dir_down ++;
+ else
+ dir_up ++;
+ }
+
+ /* If the lrealpath calls above succeeded then we should never
+ see dir_up and dir_down both being non-zero. */
+
+ len += 3 * dir_up;
+
+ if (dir_down)
+ {
+ down = pwd + strlen (pwd) - 1;
+
+ while (dir_down && down > pwd)
+ {
+ if (IS_DIR_SEPARATOR (*down))
+ --dir_down;
+ }
+ BFD_ASSERT (dir_down == 0);
+ len += strlen (down) + 1;
+ }