7 files changed, 54 insertions, 2 deletions
diff --git a/fdt_internal.h b/fdt_internal.h
index 1ac9d68..4d7ca47 100644
--- a/fdt_internal.h
+++ b/fdt_internal.h
@@ -100,12 +100,27 @@ static void *_fdt_grab_space(void *fdt, size_t len) {
   return _fdt_offset_ptr_w(fdt, offset);
 }
 
-static int _fdt_add_string(void *fdt, const char *s) {
+static const char *_fdt_find_string(const char *strtab, int tabsize,
+                                    const char *s) {
+  int len = dto_strlen(s) + 1;
+  const char *last = strtab + tabsize - len;
+  const char *p;
+
+  for (p = strtab; p <= last; p++)
+    if (dto_memcmp(p, s, len) == 0) return p;
+  return NULL;
+}
+
+static int _fdt_find_add_string(void *fdt, const char *s) {
   char *strtab = (char *)fdt + fdt_totalsize(fdt);
+  const char *p;
   int strtabsize = fdt_size_dt_strings(fdt);
   int len = dto_strlen(s) + 1;
   int struct_top, offset;
 
+  p = _fdt_find_string(strtab - strtabsize, strtabsize, s);
+  if (p) return p - strtab;
+
   /* Add it */
   offset = -strtabsize - len;
   struct_top = fdt_off_dt_struct(fdt) + fdt_size_dt_struct(fdt);
@@ -128,7 +143,7 @@ static int fast_fdt_sw_property(void *fdt, const char *name, const void *val,
   FDT_SW_CHECK_HEADER(fdt);
 
   if (*pnameoff == 0) {
-    *pnameoff = _fdt_add_string(fdt, name);
+    *pnameoff = _fdt_find_add_string(fdt, name);
     if (*pnameoff == 0) return -FDT_ERR_NOSPACE;
   }
 
diff --git a/sysdeps/include/libufdt_sysdeps.h b/sysdeps/include/libufdt_sysdeps.h
index c2682c7..fb5584f 100644
--- a/sysdeps/include/libufdt_sysdeps.h
+++ b/sysdeps/include/libufdt_sysdeps.h
@@ -48,6 +48,8 @@ unsigned long int dto_strtoul(const char *nptr, char **endptr, int base);
 
 size_t dto_strlen(const char *s);
 
+int dto_memcmp(const void *lhs, const void *rhs, size_t n);
+
 void *dto_memcpy(void *dest, const void *src, size_t n);
 
 int dto_strcmp(const char *s1, const char *s2);
diff --git a/sysdeps/libufdt_sysdeps_posix.c b/sysdeps/libufdt_sysdeps_posix.c
index c8a08f6..d7a198f 100644
--- a/sysdeps/libufdt_sysdeps_posix.c
+++ b/sysdeps/libufdt_sysdeps_posix.c
@@ -36,6 +36,10 @@ unsigned long int dto_strtoul(const char *nptr, char **endptr, int base) {
 
 size_t dto_strlen(const char *s) { return strlen(s); }
 
+int dto_memcmp(const void *lhs, const void *rhs, size_t n) {
+  return memcmp(lhs, rhs, n);
+}
+
 void *dto_memcpy(void *dest, const void *src, size_t n) {
   return memcpy(dest, src, n);
 }
diff --git a/sysdeps/libufdt_sysdeps_vendor.c b/sysdeps/libufdt_sysdeps_vendor.c
index e21a2e1..12e7695 100644
--- a/sysdeps/libufdt_sysdeps_vendor.c
+++ b/sysdeps/libufdt_sysdeps_vendor.c
@@ -194,6 +194,10 @@ unsigned long int dto_strtoul(const char *nptr, char **endptr, int base) {
 
 size_t dto_strlen(const char *s) { return strlen(s); }
 
+int dto_memcmp(const void *lhs, const void *rhs, size_t n) {
+  return memcmp(lhs, rhs, n);
+}
+
 void *dto_memcpy(void *dest, const void *src, size_t n) {
   return memcpy(dest, src, n);
 }
diff --git a/tests/run_tests.sh b/tests/run_tests.sh
index 4513950..ea3e5ba 100755
--- a/tests/run_tests.sh
+++ b/tests/run_tests.sh
@@ -69,6 +69,9 @@ main() {
   run_test_case \
     "empty_overlay" \
     "Run test about overlaying with empty base and overlay dt"
+  run_test_case \
+    "suffix_compress" \
+    "Run test about string suffix compression"
   )
 
   if [ $? -ne 0 ]; then
diff --git a/tests/testdata/suffix_compress-base.dts b/tests/testdata/suffix_compress-base.dts
new file mode 100644
index 0000000..1c51284
--- /dev/null
+++ b/tests/testdata/suffix_compress-base.dts
@@ -0,0 +1,18 @@
+/dts-v1/;
+
+/ {
+  /* these name could be suffix compressed in dtb after compiled */
+  longlonglonglonglonglonglonglonglonglonglonglongname: longlonglonglonglonglonglonglonglonglonglonglongname {};
+  longlonglonglonglonglonglonglonglonglonglongname: longlonglonglonglonglonglonglonglonglonglongname {};
+  longlonglonglonglonglonglonglonglonglongname: longlonglonglonglonglonglonglonglonglongname {};
+  longlonglonglonglonglonglonglonglongname: longlonglonglonglonglonglonglonglongname {};
+  longlonglonglonglonglonglonglongname: longlonglonglonglonglonglonglongname {};
+  longlonglonglonglonglonglongname: longlonglonglonglonglonglongname {};
+  longlonglonglonglonglongname: longlonglonglonglonglongname {};
+  longlonglonglonglongname: longlonglonglonglongname {};
+  longlonglonglongname: longlonglonglongname {};
+  longlonglongname: longlonglongname {};
+  longlongname: longlongname {};
+  longname: longname {};
+};
+
diff --git a/tests/testdata/suffix_compress-overlay.dts b/tests/testdata/suffix_compress-overlay.dts
new file mode 100644
index 0000000..382e376
--- /dev/null
+++ b/tests/testdata/suffix_compress-overlay.dts
@@ -0,0 +1,6 @@
+/dts-v1/;
+/plugin/;
+
+&longname {
+  x {};
+};