Changeset 33b8d024 in mainline for uspace/lib/posix/source/stdio/scanf.c

Timestamp:

2018-01-16T20:38:46Z (6 years ago)

Author:

Jiří Zárevúcky <zarevucky.jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

2467b41

Parents:

d39c46e0

Message:

Remove const qualifier from the argument of free() and realloc(),
as well as in numerous other variables that hold ownership of memory.

By convention, a pointer that holds ownership is _never_ qualified by const.
This is reflected in the standard type signature of free() and realloc().
Allowing const pointers to hold ownership may seem superficially convenient,
but is actually quite confusing to experienced C programmers.

File:

• uspace/lib/posix/source/stdio/scanf.c (modified) (7 diffs)

uspace/lib/posix/source/stdio/scanf.c

@@ -625 +625 @@
 
                                 const char *cur_borrowed = NULL;
+                                char *cur_duplicated = NULL;
                                 const char *cur_limited = NULL;
-                                char *cur_updated = NULL;
+                                const char *cur_updated = NULL;
 
                                 /* Borrow the cursor. Until it is returned to the provider
@@ -637 +638 @@
                                  * than allowed by width. */
                                 if (width != -1) {
-                                        cur_limited = posix_strndup(cur_borrowed, width);
+                                        cur_duplicated = posix_strndup(cur_borrowed, width);
+                                        cur_limited = cur_duplicated;
                                 } else {
                                         cur_limited = cur_borrowed;
                                 }
-                                cur_updated = (char *) cur_limited;
+                                cur_updated = cur_limited;
 
                                 long long sres = 0;
@@ -648 +650 @@
                                 /* Try to convert the integer. */
                                 if (int_conv_unsigned) {
-                                        ures = strtoull(cur_limited, &cur_updated, int_conv_base);
+                                        ures = strtoull(cur_limited, (char **) &cur_updated, int_conv_base);
                                 } else {
-                                        sres = strtoll(cur_limited, &cur_updated, int_conv_base);
+                                        sres = strtoll(cur_limited, (char **) &cur_updated, int_conv_base);
                                 }
 
                                 /* Update the cursor so it can be returned to the provider. */
                                 cur_borrowed += cur_updated - cur_limited;
-                                if (width != -1 && cur_limited != NULL) {
+                                if (cur_duplicated != NULL) {
                                         /* Deallocate duplicated part of the cursor view. */
-                                        free(cur_limited);
+                                        free(cur_duplicated);
                                 }
                                 cur_limited = NULL;
                                 cur_updated = NULL;
+                                cur_duplicated = NULL;
                                 /* Return the cursor to the provider. Input consistency is again
                                  * the job of the provider, so we can report errors from
@@ -797 +800 @@
                                 const char *cur_borrowed = NULL;
                                 const char *cur_limited = NULL;
-                                char *cur_updated = NULL;
+                                char *cur_duplicated = NULL;
+                                const char *cur_updated = NULL;
 
                                 /* Borrow the cursor. Until it is returned to the provider
@@ -808 +812 @@
                                  * than allowed by width. */
                                 if (width != -1) {
-                                        cur_limited = posix_strndup(cur_borrowed, width);
+                                        cur_duplicated = posix_strndup(cur_borrowed, width);
+                                        cur_limited = cur_duplicated;
                                 } else {
                                         cur_limited = cur_borrowed;
                                 }
-                                cur_updated = (char *) cur_limited;
+                                cur_updated = cur_limited;
 
                                 float fres = 0.0;
@@ -821 +826 @@
                                 switch (length_mod) {
                                 case LMOD_NONE:
-                                        fres = posix_strtof(cur_limited, &cur_updated);
+                                        fres = posix_strtof(cur_limited, (char **) &cur_updated);
                                         break;
                                 case LMOD_l:
-                                        dres = posix_strtod(cur_limited, &cur_updated);
+                                        dres = posix_strtod(cur_limited, (char **) &cur_updated);
                                         break;
                                 case LMOD_L:
-                                        ldres = posix_strtold(cur_limited, &cur_updated);
+                                        ldres = posix_strtold(cur_limited, (char **) &cur_updated);
                                         break;
                                 default:
@@ -835 +840 @@
                                 /* Update the cursor so it can be returned to the provider. */
                                 cur_borrowed += cur_updated - cur_limited;
-                                if (width != -1 && cur_limited != NULL) {
+                                if (cur_duplicated != NULL) {
                                         /* Deallocate duplicated part of the cursor view. */
-                                        free(cur_limited);
+                                        free(cur_duplicated);
                                 }
                                 cur_limited = NULL;