From: Kevin Day <kevin@kevux.org>
Date: Wed, 24 Jan 2024 05:53:34 +0000 (-0600)
Subject: Bugfix: Incorrect stop position is calculated when FSS content ends at the start... 
X-Git-Tag: 0.6.9~38
X-Git-Url: https://git.kevux.org/?a=commitdiff_plain;h=4d195751b4fd14fdff73e7026da92b497e174ff2;p=fll

Bugfix: Incorrect stop position is calculated when FSS content ends at the start position on FSS read operations.

When the start position is say, 0, and the determined stop position ends up being 0, then an incorrect stop range is calculated.
This happens because the stop position is subtracting one from the current position.

Add checks to ensure that the stop position is never subtracted beyond the initial start position.

The initial start position is saved at the beginning of each affected FSS read function.

This now potentially returns a start range before the stop range.
The FSS read programs should also need to be updated following this commit to handle these cases.
---

diff --git a/level_1/fl_fss/c/fss/basic.c b/level_1/fl_fss/c/fss/basic.c
index 0d58345..7dd9849 100644
--- a/level_1/fl_fss/c/fss/basic.c
+++ b/level_1/fl_fss/c/fss/basic.c
@@ -29,6 +29,7 @@ extern "C" {
     status = f_string_ranges_increase(state.step_small, found);
     if (F_status_is_error(status)) return status;
 
+    const f_number_unsigned_t begin = range->start;
     found->array[found->used].start = range->start;
 
     for (;; ++range->start) {
@@ -52,7 +53,13 @@ extern "C" {
 
     if (F_status_is_error(status)) return status;
 
-    found->array[found->used++].stop = range->start - 1;
+    if (range->start > begin) {
+      found->array[found->used++].stop = range->start - 1;
+    }
+    else {
+      found->array[found->used].start = 1;
+      found->array[found->used++].stop = 0;
+    }
 
     status = f_utf_buffer_increment(buffer, range, 1);
     if (F_status_is_error(status)) return status;
diff --git a/level_1/fl_fss/c/fss/basic_list.c b/level_1/fl_fss/c/fss/basic_list.c
index 440f583..e91b35e 100644
--- a/level_1/fl_fss/c/fss/basic_list.c
+++ b/level_1/fl_fss/c/fss/basic_list.c
@@ -26,6 +26,7 @@ extern "C" {
     status = f_string_ranges_increase(state.step_small, found);
     if (F_status_is_error(status)) return status;
 
+    const f_number_unsigned_t begin = range->start;
     found->array[found->used].start = range->start;
 
     f_array_length_t newline_last = range->start;
@@ -283,7 +284,13 @@ extern "C" {
       return F_none_stop;
     }
 
-    found->array[found->used++].stop = range->start - 1;
+    if (range->start > begin) {
+      found->array[found->used++].stop = range->start - 1;
+    }
+    else {
+      found->array[found->used].start = 1;
+      found->array[found->used++].stop = 0;
+    }
 
     return F_fss_found_content;
   }
@@ -559,6 +566,7 @@ extern "C" {
     if (status == F_none_stop) return F_data_not_stop;
 
     // Begin the search.
+    const f_number_unsigned_t begin = range->start;
     found->start = range->start;
 
     // Ignore all comment lines.
@@ -625,7 +633,7 @@ extern "C" {
 
         if (buffer.string[range->start] == f_fss_basic_list_open_s.string[0]) {
           graph_first = F_false;
-          stop = range->start - 1;
+          stop = range->start;
 
           status = f_utf_buffer_increment(buffer, range, 1);
           if (F_status_is_error(status)) return status;
@@ -684,7 +692,14 @@ extern "C" {
                 }
               } // while
 
-              found->stop = stop;
+              if (stop > begin) {
+                found->stop = stop - 1;
+              }
+              else {
+                found->start = 1;
+                found->stop = 0;
+              }
+
               range->start = start + 1;
 
               return F_fss_found_object;
@@ -714,7 +729,7 @@ extern "C" {
 
       if (buffer.string[range->start] == f_fss_basic_list_open_s.string[0]) {
         graph_first = F_false;
-        stop = range->start - 1;
+        stop = range->start;
 
         status = f_utf_buffer_increment(buffer, range, 1);
         if (F_status_is_error(status)) break;
@@ -745,7 +760,13 @@ extern "C" {
         private_macro_fl_fss_object_return_on_overflow_delimited((buffer), (*range), (*found), F_none_eos, F_none_stop);
 
         if (buffer.string[range->start] == f_fss_eol_s.string[0]) {
-          found->stop = stop;
+          if (stop > begin) {
+            found->stop = stop - 1;
+          }
+          else {
+            found->start = 1;
+            found->stop = 0;
+          }
 
           status = f_utf_buffer_increment(buffer, range, 1);
           if (F_status_is_error(status)) break;
diff --git a/level_1/fl_fss/c/fss/embedded_list.c b/level_1/fl_fss/c/fss/embedded_list.c
index dd24130..fc53776 100644
--- a/level_1/fl_fss/c/fss/embedded_list.c
+++ b/level_1/fl_fss/c/fss/embedded_list.c
@@ -987,6 +987,7 @@ extern "C" {
     }
 
     // Begin the search.
+    const f_number_unsigned_t begin = range->start;
     found->start = range->start;
 
     // Ignore all comment lines.
@@ -1059,7 +1060,7 @@ extern "C" {
 
         if (buffer.string[range->start] == f_fss_embedded_list_open_s.string[0]) {
           graph_first = F_false;
-          stop = range->start++ - 1;
+          stop = range->start++;
 
           while (range->start <= range->stop && range->start < buffer.used) {
 
@@ -1111,7 +1112,14 @@ extern "C" {
 
               if (F_status_is_error(status)) break;
 
-              found->stop = stop;
+              if (stop > begin) {
+                found->stop = stop - 1;
+              }
+              else {
+                found->start = 1;
+                found->stop = 0;
+              }
+
               range->start = start + 1;
 
               return F_fss_found_object;
@@ -1139,7 +1147,7 @@ extern "C" {
       }
       else if (buffer.string[range->start] == f_fss_embedded_list_open_s.string[0]) {
         graph_first = F_false;
-        stop = range->start - 1;
+        stop = range->start;
 
         status = f_utf_buffer_increment(buffer, range, 1);
         if (F_status_is_error(status)) break;
@@ -1172,7 +1180,13 @@ extern "C" {
         private_macro_fl_fss_object_return_on_overflow_delimited((buffer), (*range), (*found), F_none_eos, F_none_stop);
 
         if (buffer.string[range->start] == f_fss_eol_s.string[0]) {
-          found->stop = stop;
+          if (stop > begin) {
+            found->stop = stop - 1;
+          }
+          else {
+            found->start = 1;
+            found->stop = 0;
+          }
 
           // Move the start position to after the EOL.
           ++range->start;
diff --git a/level_1/fl_fss/c/fss/extended_list.c b/level_1/fl_fss/c/fss/extended_list.c
index 3860df2..f3eb721 100644
--- a/level_1/fl_fss/c/fss/extended_list.c
+++ b/level_1/fl_fss/c/fss/extended_list.c
@@ -548,6 +548,7 @@ extern "C" {
     }
 
     // Begin the search.
+    const f_number_unsigned_t begin = range->start;
     found->start = range->start;
 
     // Ignore all comment lines.
@@ -620,7 +621,7 @@ extern "C" {
 
         if (buffer.string[range->start] == f_fss_extended_list_open_s.string[0]) {
           graph_first = F_false;
-          stop = range->start++ - 1;
+          stop = range->start++;
 
           while (range->start <= range->stop && range->start < buffer.used) {
 
@@ -671,7 +672,14 @@ extern "C" {
 
               if (F_status_is_error(status)) break;
 
-              found->stop = stop;
+              if (stop > begin) {
+                found->stop = stop - 1;
+              }
+              else {
+                found->start = 1;
+                found->stop = 0;
+              }
+
               range->start = start + 1;
 
               return F_fss_found_object;
@@ -700,7 +708,7 @@ extern "C" {
       }
       else if (buffer.string[range->start] == f_fss_extended_list_open_s.string[0]) {
         graph_first = F_false;
-        stop = range->start - 1;
+        stop = range->start;
 
         status = f_utf_buffer_increment(buffer, range, 1);
         if (F_status_is_error(status)) break;
@@ -733,7 +741,13 @@ extern "C" {
         private_macro_fl_fss_object_return_on_overflow_delimited((buffer), (*range), (*found), F_none_eos, F_none_stop);
 
         if (buffer.string[range->start] == f_fss_eol_s.string[0]) {
-          found->stop = stop;
+          if (stop > begin) {
+            found->stop = stop - 1;
+          }
+          else {
+            found->start = 1;
+            found->stop = 0;
+          }
 
           // Move the start position to after the EOL.
           ++range->start;