AK: Make string-to-number conversion helpers return Optional

Get rid of the weird old signature:

- int StringType::to_int(bool& ok) const

And replace it with sensible new signature:

- Optional<int> StringType::to_int() const

Userland/allocate.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Optional.h>
 #include <AK/String.h>
 #include <LibCore/ElapsedTimer.h>
 #include <stdio.h>
@@ -36,7 +37,9 @@ void usage(void)
     exit(1);
 }
 
-enum Unit { Bytes, KiloBytes, MegaBytes };
+enum Unit { Bytes,
+    KiloBytes,
+    MegaBytes };
 
 int main(int argc, char** argv)
 {
@@ -44,11 +47,11 @@ int main(int argc, char** argv)
     Unit unit = MegaBytes;
 
     if (argc >= 2) {
-        bool ok;
-        count = String(argv[1]).to_uint(ok);
-        if (!ok) {
+        auto number = String(argv[1]).to_uint();
+        if (!number.has_value()) {
             usage();
         }
+        count = number.value();
     }
 
     if (argc >= 3) {

Userland/chgrp.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Optional.h>
 #include <AK/String.h>
 #include <grp.h>
 #include <pwd.h>
@@ -52,10 +53,11 @@ int main(int argc, char** argv)
         return 1;
     }
 
-    bool ok;
-    new_gid = gid_arg.to_uint(ok);
+    auto number = gid_arg.to_uint();
 
-    if (!ok) {
+    if (number.has_value()) {
+        new_gid = number.value();
+    } else {
         auto* group = getgrnam(gid_arg.characters());
         if (!group) {
             fprintf(stderr, "Unknown group '%s'\n", gid_arg.characters());

Userland/chown.cpp

@@ -54,9 +54,10 @@ int main(int argc, char** argv)
         return 1;
     }
 
-    bool ok;
-    new_uid = parts[0].to_uint(ok);
-    if (!ok) {
+    auto number = parts[0].to_uint();
+    if (number.has_value()) {
+        new_uid = number.value();
+    } else {
         auto* passwd = getpwnam(parts[0].characters());
         if (!passwd) {
             fprintf(stderr, "Unknown user '%s'\n", parts[0].characters());
@@ -66,8 +67,10 @@ int main(int argc, char** argv)
     }
 
     if (parts.size() == 2) {
-        new_gid = parts[1].to_uint(ok);
-        if (!ok) {
+        auto number = parts[1].to_uint();
+        if (number.has_value()) {
+            new_gid = number.value();
+        } else {
             auto* group = getgrnam(parts[1].characters());
             if (!new_gid) {
                 fprintf(stderr, "Unknown group '%s'\n", parts[1].characters());

Userland/cut.cpp

@@ -89,74 +89,70 @@ static void expand_list(Vector<String>& tokens, Vector<Index>& indexes)
         }
 
         if (token[0] == '-') {
-            bool ok = true;
-            ssize_t index = token.substring(1, token.length() - 1).to_int(ok);
-            if (!ok) {
+            auto index = token.substring(1, token.length() - 1).to_int();
+            if (!index.has_value()) {
                 fprintf(stderr, "cut: invalid byte/character position '%s'\n", token.characters());
                 print_usage_and_exit(1);
             }
 
-            if (index == 0) {
+            if (index.value() == 0) {
                 fprintf(stderr, "cut: byte/character positions are numbered from 1\n");
                 print_usage_and_exit(1);
             }
 
-            Index tmp = { 1, index, Index::Type::RangedIndex };
+            Index tmp = { 1, index.value(), Index::Type::RangedIndex };
             add_if_not_exists(indexes, tmp);
         } else if (token[token.length() - 1] == '-') {
-            bool ok = true;
-            ssize_t index = token.substring(0, token.length() - 1).to_int(ok);
-            if (!ok) {
+            auto index = token.substring(0, token.length() - 1).to_int();
+            if (!index.has_value()) {
                 fprintf(stderr, "cut: invalid byte/character position '%s'\n", token.characters());
                 print_usage_and_exit(1);
             }
 
-            if (index == 0) {
+            if (index.value() == 0) {
                 fprintf(stderr, "cut: byte/character positions are numbered from 1\n");
                 print_usage_and_exit(1);
             }
-            Index tmp = { index, -1, Index::Type::SliceIndex };
+            Index tmp = { index.value(), -1, Index::Type::SliceIndex };
             add_if_not_exists(indexes, tmp);
         } else {
             auto range = token.split('-');
             if (range.size() == 2) {
-                bool ok = true;
-                ssize_t index1 = range[0].to_int(ok);
-                if (!ok) {
+                auto index1 = range[0].to_int();
+                if (!index1.has_value()) {
                     fprintf(stderr, "cut: invalid byte/character position '%s'\n", range[0].characters());
                     print_usage_and_exit(1);
                 }
 
-                ssize_t index2 = range[1].to_int(ok);
-                if (!ok) {
+                auto index2 = range[1].to_int();
+                if (!index2.has_value()) {
                     fprintf(stderr, "cut: invalid byte/character position '%s'\n", range[1].characters());
                     print_usage_and_exit(1);
                 }
 
-                if (index1 > index2) {
+                if (index1.value() > index2.value()) {
                     fprintf(stderr, "cut: invalid decreasing range\n");
                     print_usage_and_exit(1);
-                } else if (index1 == 0 || index2 == 0) {
+                } else if (index1.value() == 0 || index2.value() == 0) {
                     fprintf(stderr, "cut: byte/character positions are numbered from 1\n");
                     print_usage_and_exit(1);
                 }
 
-                Index tmp = { index1, index2, Index::Type::RangedIndex };
+                Index tmp = { index1.value(), index2.value(), Index::Type::RangedIndex };
                 add_if_not_exists(indexes, tmp);
             } else if (range.size() == 1) {
-                bool ok = true;
-                ssize_t index = range[0].to_int(ok);
-                if (!ok) {
+                auto index = range[0].to_int();
+                if (!index.has_value()) {
                     fprintf(stderr, "cut: invalid byte/character position '%s'\n", range[0].characters());
                     print_usage_and_exit(1);
                 }
 
-                if (index == 0) {
+                if (index.value() == 0) {
                     fprintf(stderr, "cut: byte/character positions are numbered from 1\n");
                     print_usage_and_exit(1);
                 }
 
-                Index tmp = { index, index, Index::Type::SingleIndex };
+                Index tmp = { index.value(), index.value(), Index::Type::SingleIndex };
                 add_if_not_exists(indexes, tmp);
             } else {
                 fprintf(stderr, "cut: invalid byte or character range\n");

Userland/date.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Optional.h>
 #include <AK/String.h>
 #include <LibCore/DateTime.h>
 #include <stdio.h>
@@ -44,12 +45,12 @@ int main(int argc, char** argv)
         return 0;
     }
     if (argc == 3 && !strcmp(argv[1], "-s")) {
-        bool ok;
-        timespec ts = { String(argv[2]).to_uint(ok), 0 };
-        if (!ok) {
+        auto number = StringView(argv[2]).to_uint();
+        if (!number.has_value()) {
             fprintf(stderr, "date: Invalid timestamp value");
             return 1;
         }
+        timespec ts = { number.value(), 0 };
         if (clock_settime(CLOCK_REALTIME, &ts) < 0) {
             perror("clock_settime");
             return 1;

Userland/find.cpp

@@ -120,10 +120,10 @@ class LinksCommand final : public StatCommand {
 public:
     LinksCommand(const char* arg)
     {
-        bool ok;
-        m_links = StringView(arg).to_uint(ok);
-        if (!ok)
+        auto number = StringView(arg).to_uint();
+        if (!number.has_value())
             fatal_error("Invalid number: \033[1m%s", arg);
+        m_links = number.value();
     }
 
 private:
@@ -143,10 +143,10 @@ public:
             m_uid = passwd->pw_uid;
         } else {
             // Attempt to parse it as decimal UID.
-            bool ok;
-            m_uid = StringView(arg).to_uint(ok);
-            if (!ok)
+            auto number =  StringView(arg).to_uint();
+            if (!number.has_value())
                 fatal_error("Invalid user: \033[1m%s", arg);
+            m_uid = number.value();
         }
     }
 
@@ -167,10 +167,10 @@ public:
             m_gid = gr->gr_gid;
         } else {
             // Attempt to parse it as decimal GID.
-            bool ok;
-            m_gid = StringView(arg).to_int(ok);
-            if (!ok)
+            auto number = StringView(arg).to_int();
+            if (!number.has_value())
                 fatal_error("Invalid group: \033[1m%s", arg);
+            m_gid = number.value();
         }
     }
 
@@ -192,10 +192,10 @@ public:
             m_is_bytes = true;
             view = view.substring_view(0, view.length() - 1);
         }
-        bool ok;
-        m_size = view.to_uint(ok);
-        if (!ok)
+        auto number = view.to_uint();
+        if (!number.has_value())
             fatal_error("Invalid size: \033[1m%s", arg);
+        m_size = number.value();
     }
 
 private:

Userland/kill.cpp

@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <AK/Optional.h>
 #include <AK/String.h>
 #include <signal.h>
 #include <stdio.h>
@@ -45,24 +46,25 @@ int main(int argc, char** argv)
 
     if (argc != 2 && argc != 3)
         print_usage_and_exit();
-    bool ok;
     unsigned signum = SIGTERM;
     int pid_argi = 1;
     if (argc == 3) {
         pid_argi = 2;
         if (argv[1][0] != '-')
             print_usage_and_exit();
-        signum = String(&argv[1][1]).to_uint(ok);
-        if (!ok) {
+        auto number = StringView(&argv[1][1]).to_uint();
+        if (!number.has_value()) {
             printf("'%s' is not a valid signal number\n", &argv[1][1]);
             return 2;
         }
+        signum = number.value();
     }
-    pid_t pid = String(argv[pid_argi]).to_int(ok);
-    if (!ok) {
+    auto pid_opt = String(argv[pid_argi]).to_int();
+    if (!pid_opt.has_value()) {
         printf("'%s' is not a valid PID\n", argv[pid_argi]);
         return 3;
     }
+    pid_t pid = pid_opt.value();
 
     int rc = kill(pid, signum);
     if (rc < 0)

Userland/killall.cpp

@@ -54,7 +54,6 @@ static int kill_all(const String& process_name, const unsigned signum)
 
 int main(int argc, char** argv)
 {
-    bool ok;
     unsigned signum = SIGTERM;
     int name_argi = 1;
 
@@ -67,11 +66,12 @@ int main(int argc, char** argv)
         if (argv[1][0] != '-')
             print_usage_and_exit();
 
-        signum = String(&argv[1][1]).to_uint(ok);
-        if (!ok) {
+        auto number = String(&argv[1][1]).to_uint();
+        if (!number.has_value()) {
             printf("'%s' is not a valid signal number\n", &argv[1][1]);
             return 2;
         }
+        signum = number.value();
     }
 
     return kill_all(argv[name_argi], signum);

Userland/pidof.cpp

@@ -74,15 +74,16 @@ int main(int argc, char** argv)
 
     pid_t pid_to_omit = 0;
     if (omit_pid_value) {
-        bool ok = true;
-        if (!strcmp(omit_pid_value, "%PPID"))
+        if (!strcmp(omit_pid_value, "%PPID")) {
             pid_to_omit = getppid();
-        else
-            pid_to_omit = StringView(omit_pid_value).to_uint(ok);
-        if (!ok) {
-            fprintf(stderr, "Invalid value for -o\n");
-            args_parser.print_usage(stderr, argv[0]);
-            return 1;
+        } else {
+            auto number = StringView(omit_pid_value).to_uint();
+            if (!number.has_value()) {
+                fprintf(stderr, "Invalid value for -o\n");
+                args_parser.print_usage(stderr, argv[0]);
+                return 1;
+            }
+            pid_to_omit = number.value();
         }
     }
     return pid_of(process_name, single_shot, omit_pid_value != nullptr, pid_to_omit);

Userland/truncate.cpp

@@ -75,12 +75,12 @@ int main(int argc, char** argv)
             break;
         }
 
-        bool ok;
-        size = str.to_int(ok);
-        if (!ok) {
+        auto size_opt = str.to_int();
+        if (!size_opt.has_value()) {
             args_parser.print_usage(stderr, argv[0]);
             return 1;
         }
+        size = size_opt.value();
     }
 
     if (reference) {