1 files changed, 36 insertions, 28 deletions

diff --git a/miscutils/bc.c b/miscutils/bc.c
index 6ab3a4252..5a4c92a1c 100644
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -2976,29 +2976,40 @@ static void bc_lex_whitespace(BcLex *l)
 static BC_STATUS zbc_lex_number(BcLex *l, char start)
 {
         const char *buf = l->buf + l->i;
-        size_t len, hits = 0, bslashes = 0, i = 0, j;
-        char c = buf[i];
-        bool last_pt, pt = start == '.';
+        size_t len, bslashes, i, ccnt;
+        bool pt;
 
-        last_pt = pt;
+        pt = (start == '.');
         l->t.t = BC_LEX_NUMBER;
-
-        while (c != 0 && (isdigit(c) || (c >= 'A' && c <= 'F') ||
-                          (c == '.' && !pt) || (c == '\\' && buf[i + 1] == '\n')))
-        {
-                if (c != '\\') {
-                        last_pt = c == '.';
-                        pt = pt || last_pt;
+        bslashes = 0;
+        ccnt = i = 0;
+        for (;;) {
+                char c = buf[i];
+                if (c == '\0')
+                        break;
+                if (c == '\\' && buf[i + 1] == '\n') {
+                        i += 2;
+                        bslashes++;
+                        continue;
                 }
-                else {
-                        ++i;
-                        bslashes += 1;
+                if (!isdigit(c) && (c < 'A' || c > 'F')) {
+                        if (c != '.') break;
+                        // if '.' was already seen, stop on second one:
+                        if (pt) break;
+                        pt = 1;
                 }
-
-                c = buf[++i];
+                // buf[i] is one of "0-9A-F."
+                i++;
+                if (c != '.')
+                        ccnt = i;
         }
+        //i is buf[i] index of the first not-yet-parsed char
+        l->i += i;
+
+        //ccnt is the number of chars in the number string, excluding possible
+        //trailing "." and possible following trailing "\<newline>"(s).
+        len = ccnt - bslashes * 2 + 1; // +1 byte for NUL termination
 
-        len = i + !last_pt - bslashes * 2;
         // This check makes sense only if size_t is (much) larger than BC_MAX_NUM.
         if (SIZE_MAX > (BC_MAX_NUM | 0xff)) {
                 if (len > BC_MAX_NUM)
@@ -3006,26 +3017,23 @@ static BC_STATUS zbc_lex_number(BcLex *l, char start)
         }
 
         bc_vec_pop_all(&l->t.v);
-        bc_vec_expand(&l->t.v, len + 1);
+        bc_vec_expand(&l->t.v, 1 + len);
         bc_vec_push(&l->t.v, &start);
 
-        for (buf -= 1, j = 1; j < len + hits * 2; ++j) {
-
-                c = buf[j];
-
+        while (ccnt != 0) {
                 // If we have hit a backslash, skip it. We don't have
                 // to check for a newline because it's guaranteed.
-                if (hits < bslashes && c == '\\') {
-                        ++hits;
-                        ++j;
+                if (*buf == '\\') {
+                        buf += 2;
+                        ccnt -= 2;
                         continue;
                 }
-
-                bc_vec_push(&l->t.v, &c);
+                bc_vec_push(&l->t.v, buf);
+                buf++;
+                ccnt--;
         }
 
         bc_vec_pushZeroByte(&l->t.v);
-        l->i += i;
 
         RETURN_STATUS(BC_STATUS_SUCCESS);
 }