libc

cleonos/c/apps/cat_main.c

@@ -1,4 +1,6 @@
 #include "cmd_runtime.h"
+#include <stdio.h>
+
 static int ush_cmd_cat(const ush_state *sh, const char *arg) {
     char path[USH_PATH_MAX];
     char buf[USH_CAT_MAX + 1ULL];
@@ -8,28 +10,28 @@ static int ush_cmd_cat(const ush_state *sh, const char *arg) {
 
     if (arg == (const char *)0 || arg[0] == '\0') {
         if (ush_pipeline_stdin_text != (const char *)0 && ush_pipeline_stdin_len > 0ULL) {
-            ush_write(ush_pipeline_stdin_text);
+            (void)fputs(ush_pipeline_stdin_text, 1);
             return 1;
         }
 
-        ush_writeln("cat: file path required");
+        (void)puts("cat: file path required");
         return 0;
     }
 
     if (ush_resolve_path(sh, arg, path, (u64)sizeof(path)) == 0) {
-        ush_writeln("cat: invalid path");
+        (void)puts("cat: invalid path");
         return 0;
     }
 
     if (cleonos_sys_fs_stat_type(path) != 1ULL) {
-        ush_writeln("cat: file not found");
+        (void)puts("cat: file not found");
         return 0;
     }
 
     size = cleonos_sys_fs_stat_size(path);
 
     if (size == (u64)-1) {
-        ush_writeln("cat: failed to stat file");
+        (void)puts("cat: failed to stat file");
         return 0;
     }
 
@@ -41,7 +43,7 @@ static int ush_cmd_cat(const ush_state *sh, const char *arg) {
     got = cleonos_sys_fs_read(path, buf, req);
 
     if (got == 0ULL) {
-        ush_writeln("cat: read failed");
+        (void)puts("cat: read failed");
         return 0;
     }
 
@@ -50,10 +52,10 @@ static int ush_cmd_cat(const ush_state *sh, const char *arg) {
     }
 
     buf[got] = '\0';
-    ush_writeln(buf);
+    (void)puts(buf);
 
     if (size > got) {
-        ush_writeln("[cat] output truncated");
+        (void)puts("[cat] output truncated");
     }
 
     return 1;

cleonos/c/apps/cmd_runtime.c

@@ -4,16 +4,10 @@ const char *ush_pipeline_stdin_text = (const char *)0;
 u64 ush_pipeline_stdin_len = 0ULL;
 
 void ush_zero(void *ptr, u64 size) {
-    u64 i;
-    char *bytes = (char *)ptr;
-
-    if (bytes == (char *)0) {
+    if (ptr == (void *)0 || size == 0ULL) {
         return;
     }
-
-    for (i = 0ULL; i < size; i++) {
-        bytes[i] = 0;
-    }
+    (void)memset(ptr, 0, (size_t)size);
 }
 
 void ush_init_state(ush_state *sh) {
@@ -27,84 +21,47 @@ void ush_init_state(ush_state *sh) {
 }
 
 u64 ush_strlen(const char *str) {
-    u64 len = 0ULL;
-
-    if (str == (const char *)0) {
-        return 0ULL;
-    }
-
-    while (str[len] != '\0') {
-        len++;
-    }
-
-    return len;
+    return (str == (const char *)0) ? 0ULL : (u64)strlen(str);
 }
 
 int ush_streq(const char *left, const char *right) {
-    u64 i = 0ULL;
-
     if (left == (const char *)0 || right == (const char *)0) {
         return 0;
     }
-
-    while (left[i] != '\0' && right[i] != '\0') {
-        if (left[i] != right[i]) {
-            return 0;
-        }
-        i++;
-    }
-
-    return (left[i] == right[i]) ? 1 : 0;
+    return (strcmp(left, right) == 0) ? 1 : 0;
 }
 
 int ush_is_space(char ch) {
-    return (ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n') ? 1 : 0;
+    return (isspace((unsigned char)ch) != 0) ? 1 : 0;
 }
 
 int ush_is_printable(char ch) {
-    return (ch >= 32 && ch <= 126) ? 1 : 0;
+    return (isprint((unsigned char)ch) != 0) ? 1 : 0;
 }
 
 int ush_has_suffix(const char *name, const char *suffix) {
-    u64 name_len;
-    u64 suffix_len;
-    u64 i;
+    size_t name_len;
+    size_t suffix_len;
 
     if (name == (const char *)0 || suffix == (const char *)0) {
         return 0;
     }
 
-    name_len = ush_strlen(name);
-    suffix_len = ush_strlen(suffix);
+    name_len = strlen(name);
+    suffix_len = strlen(suffix);
 
     if (suffix_len > name_len) {
         return 0;
     }
 
-    for (i = 0ULL; i < suffix_len; i++) {
-        if (name[name_len - suffix_len + i] != suffix[i]) {
-            return 0;
-        }
-    }
-
-    return 1;
+    return (strncmp(name + (name_len - suffix_len), suffix, suffix_len) == 0) ? 1 : 0;
 }
 
 int ush_contains_char(const char *text, char needle) {
-    u64 i = 0ULL;
-
     if (text == (const char *)0) {
         return 0;
     }
-
-    while (text[i] != '\0') {
-        if (text[i] == needle) {
-            return 1;
-        }
-        i++;
-    }
-
-    return 0;
+    return (strchr(text, (int)needle) != (char *)0) ? 1 : 0;
 }
 
 int ush_parse_u64_dec(const char *text, u64 *out_value) {
@@ -118,7 +75,7 @@ int ush_parse_u64_dec(const char *text, u64 *out_value) {
     while (text[i] != '\0') {
         u64 digit;
 
-        if (text[i] < '0' || text[i] > '9') {
+        if (isdigit((unsigned char)text[i]) == 0) {
             return 0;
         }
 
@@ -137,45 +94,34 @@ int ush_parse_u64_dec(const char *text, u64 *out_value) {
 }
 
 void ush_copy(char *dst, u64 dst_size, const char *src) {
-    u64 i = 0ULL;
-
     if (dst == (char *)0 || src == (const char *)0 || dst_size == 0ULL) {
         return;
     }
-
-    while (src[i] != '\0' && i + 1ULL < dst_size) {
-        dst[i] = src[i];
-        i++;
-    }
-
-    dst[i] = '\0';
+    (void)strncpy(dst, src, (size_t)(dst_size - 1ULL));
+    dst[dst_size - 1ULL] = '\0';
 }
 
 void ush_trim_line(char *line) {
-    u64 start = 0ULL;
-    u64 i = 0ULL;
-    u64 len;
+    size_t start = 0U;
+    size_t len;
 
     if (line == (char *)0) {
         return;
     }
 
-    while (line[start] != '\0' && ush_is_space(line[start]) != 0) {
+    while (line[start] != '\0' && isspace((unsigned char)line[start]) != 0) {
         start++;
     }
 
-    if (start > 0ULL) {
-        while (line[start + i] != '\0') {
-            line[i] = line[start + i];
-            i++;
-        }
-        line[i] = '\0';
+    if (start > 0U) {
+        size_t remain = strlen(line + start) + 1U;
+        (void)memmove(line, line + start, remain);
     }
 
-    len = ush_strlen(line);
+    len = strlen(line);
 
-    while (len > 0ULL && ush_is_space(line[len - 1ULL]) != 0) {
-        line[len - 1ULL] = '\0';
+    while (len > 0U && isspace((unsigned char)line[len - 1U]) != 0) {
+        line[len - 1U] = '\0';
         len--;
     }
 }
@@ -220,37 +166,14 @@ void ush_parse_line(const char *line, char *out_cmd, u64 cmd_size, char *out_arg
 }
 
 void ush_write(const char *text) {
-    u64 len;
-    const char *cursor;
-    u64 left;
-
     if (text == (const char *)0) {
         return;
     }
-
-    len = ush_strlen(text);
-
-    if (len == 0ULL) {
-        return;
-    }
-
-    cursor = text;
-    left = len;
-
-    while (left > 0ULL) {
-        u64 wrote = cleonos_sys_fd_write(1ULL, cursor, left);
-
-        if (wrote == 0ULL || wrote == (u64)-1) {
-            break;
-        }
-
-        cursor += wrote;
-        left -= wrote;
-    }
+    (void)fputs(text, 1);
 }
 
 void ush_write_char(char ch) {
-    (void)cleonos_sys_fd_write(1ULL, &ch, 1ULL);
+    (void)fputc((int)(unsigned char)ch, 1);
 }
 
 void ush_writeln(const char *text) {
@@ -470,11 +393,9 @@ int ush_path_is_under_system(const char *path) {
     if (path == (const char *)0) {
         return 0;
     }
-
-    if (path[0] != '/' || path[1] != 's' || path[2] != 'y' || path[3] != 's' || path[4] != 't' || path[5] != 'e' || path[6] != 'm') {
+    if (strncmp(path, "/system", 7U) != 0) {
         return 0;
     }
-
     return (path[7] == '\0' || path[7] == '/') ? 1 : 0;
 }
 
@@ -482,11 +403,9 @@ int ush_path_is_under_temp(const char *path) {
     if (path == (const char *)0) {
         return 0;
     }
-
-    if (path[0] != '/' || path[1] != 't' || path[2] != 'e' || path[3] != 'm' || path[4] != 'p') {
+    if (strncmp(path, "/temp", 5U) != 0) {
         return 0;
     }
-
     return (path[5] == '\0' || path[5] == '/') ? 1 : 0;
 }
 

cleonos/c/apps/cmd_runtime.h

@@ -2,6 +2,10 @@
 #define CLEONOS_CMD_RUNTIME_H
 
 #include <cleonos_syscall.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
 typedef long long i64;
 

cleonos/c/apps/grep_main.c

@@ -1,10 +1,12 @@
 #include "cmd_runtime.h"
+#include <stdio.h>
+
 static void ush_grep_write_u64_dec(u64 value) {
     char tmp[32];
     u64 len = 0ULL;
 
     if (value == 0ULL) {
-        ush_write_char('0');
+        (void)putchar('0');
         return;
     }
 
@@ -15,7 +17,7 @@ static void ush_grep_write_u64_dec(u64 value) {
 
     while (len > 0ULL) {
         len--;
-        ush_write_char(tmp[len]);
+        (void)putchar((unsigned char)tmp[len]);
     }
 }
 
@@ -73,14 +75,14 @@ static u64 ush_grep_emit_matches(const char *input, u64 input_len, const char *p
 
                 if (with_line_number != 0) {
                     ush_grep_write_u64_dec(line_no);
-                    ush_write(":");
+                    (void)fputs(":", 1);
                 }
 
                 for (j = 0ULL; j < line_len; j++) {
-                    ush_write_char(input[start + j]);
+                    (void)putchar((unsigned char)input[start + j]);
                 }
 
-                ush_write_char('\n');
+                (void)putchar('\n');
             }
 
             start = i + 1ULL;
@@ -108,12 +110,12 @@ static int ush_cmd_grep(const ush_state *sh, const char *arg) {
     static char file_buf[USH_COPY_MAX + 1U];
 
     if (sh == (const ush_state *)0 || arg == (const char *)0 || arg[0] == '\0') {
-        ush_writeln("grep: usage grep [-n] <pattern> [file]");
+        (void)puts("grep: usage grep [-n] <pattern> [file]");
         return 0;
     }
 
     if (ush_split_first_and_rest(arg, first, (u64)sizeof(first), &rest) == 0) {
-        ush_writeln("grep: usage grep [-n] <pattern> [file]");
+        (void)puts("grep: usage grep [-n] <pattern> [file]");
         return 0;
     }
 
@@ -121,7 +123,7 @@ static int ush_cmd_grep(const ush_state *sh, const char *arg) {
         with_line_number = 1;
 
         if (ush_split_first_and_rest(rest, second, (u64)sizeof(second), &rest2) == 0) {
-            ush_writeln("grep: usage grep [-n] <pattern> [file]");
+            (void)puts("grep: usage grep [-n] <pattern> [file]");
             return 0;
         }
 
@@ -133,43 +135,43 @@ static int ush_cmd_grep(const ush_state *sh, const char *arg) {
 
     if (rest != (const char *)0 && rest[0] != '\0') {
         if (ush_split_first_and_rest(rest, third, (u64)sizeof(third), &rest2) == 0) {
-            ush_writeln("grep: usage grep [-n] <pattern> [file]");
+            (void)puts("grep: usage grep [-n] <pattern> [file]");
             return 0;
         }
 
         file_arg = third;
 
         if (rest2 != (const char *)0 && rest2[0] != '\0') {
-            ush_writeln("grep: usage grep [-n] <pattern> [file]");
+            (void)puts("grep: usage grep [-n] <pattern> [file]");
             return 0;
         }
     }
 
     if (pattern == (const char *)0 || pattern[0] == '\0') {
-        ush_writeln("grep: pattern required");
+        (void)puts("grep: pattern required");
         return 0;
     }
 
     if (file_arg != (const char *)0) {
         if (ush_resolve_path(sh, file_arg, path, (u64)sizeof(path)) == 0) {
-            ush_writeln("grep: invalid path");
+            (void)puts("grep: invalid path");
             return 0;
         }
 
         if (cleonos_sys_fs_stat_type(path) != 1ULL) {
-            ush_writeln("grep: file not found");
+            (void)puts("grep: file not found");
             return 0;
         }
 
         size = cleonos_sys_fs_stat_size(path);
 
         if (size == (u64)-1) {
-            ush_writeln("grep: failed to stat file");
+            (void)puts("grep: failed to stat file");
             return 0;
         }
 
         if (size > (u64)USH_COPY_MAX) {
-            ush_writeln("grep: file too large for user buffer");
+            (void)puts("grep: file too large for user buffer");
             return 0;
         }
 
@@ -180,7 +182,7 @@ static int ush_cmd_grep(const ush_state *sh, const char *arg) {
         got = cleonos_sys_fs_read(path, file_buf, size);
 
         if (got == 0ULL || got != size) {
-            ush_writeln("grep: read failed");
+            (void)puts("grep: read failed");
             return 0;
         }
 
@@ -189,7 +191,7 @@ static int ush_cmd_grep(const ush_state *sh, const char *arg) {
         input_len = got;
     } else {
         if (ush_pipeline_stdin_text == (const char *)0) {
-            ush_writeln("grep: file path required (or pipeline input)");
+            (void)puts("grep: file path required (or pipeline input)");
             return 0;
         }
 

cleonos/c/apps/head_main.c

@@ -1,4 +1,5 @@
 #include "cmd_runtime.h"
+#include <stdio.h>
 
 static int ush_head_parse_args(const char *arg, u64 *out_line_count, char *out_file, u64 out_file_size) {
     char first[USH_PATH_MAX];
@@ -69,24 +70,24 @@ static int ush_head_load_input(const ush_state *sh, const char *file_arg, const
 
     if (file_arg != (const char *)0 && file_arg[0] != '\0') {
         if (ush_resolve_path(sh, file_arg, path, (u64)sizeof(path)) == 0) {
-            ush_writeln("head: invalid path");
+            (void)puts("head: invalid path");
             return 0;
         }
 
         if (cleonos_sys_fs_stat_type(path) != 1ULL) {
-            ush_writeln("head: file not found");
+            (void)puts("head: file not found");
             return 0;
         }
 
         size = cleonos_sys_fs_stat_size(path);
 
         if (size == (u64)-1) {
-            ush_writeln("head: failed to stat file");
+            (void)puts("head: failed to stat file");
             return 0;
         }
 
         if (size > (u64)USH_COPY_MAX) {
-            ush_writeln("head: file too large for user buffer");
+            (void)puts("head: file too large for user buffer");
             return 0;
         }
 
@@ -100,7 +101,7 @@ static int ush_head_load_input(const ush_state *sh, const char *file_arg, const
         got = cleonos_sys_fs_read(path, file_buf, size);
 
         if (got == 0ULL || got != size) {
-            ush_writeln("head: read failed");
+            (void)puts("head: read failed");
             return 0;
         }
 
@@ -111,7 +112,7 @@ static int ush_head_load_input(const ush_state *sh, const char *file_arg, const
     }
 
     if (ush_pipeline_stdin_text == (const char *)0) {
-        ush_writeln("head: file path required (or pipeline input)");
+        (void)puts("head: file path required (or pipeline input)");
         return 0;
     }
 
@@ -133,7 +134,7 @@ static void ush_head_emit(const char *input, u64 input_len, u64 line_count) {
             break;
         }
 
-        ush_write_char(input[i]);
+        (void)putchar((unsigned char)input[i]);
 
         if (input[i] == '\n') {
             emitted++;
@@ -152,7 +153,7 @@ static int ush_cmd_head(const ush_state *sh, const char *arg) {
     }
 
     if (ush_head_parse_args(arg, &line_count, file_arg, (u64)sizeof(file_arg)) == 0) {
-        ush_writeln("head: usage head [-n N] [file]");
+        (void)puts("head: usage head [-n N] [file]");
         return 0;
     }
 

cleonos/c/apps/hello_main.c

@@ -1,7 +1,6 @@
-#include <cleonos_syscall.h>
+#include <stdio.h>
 
 int cleonos_app_main(void) {
-    static const char msg[] = "[USER][HELLO] Hello world from /hello.elf\n";
-    (void)cleonos_sys_fd_write(1ULL, msg, (u64)(sizeof(msg) - 1U));
+    (void)printf("[USER][HELLO] Hello world from %s\n", "/hello.elf");
     return 0;
 }

cleonos/c/apps/ls_main.c

@@ -1,4 +1,23 @@
 #include "cmd_runtime.h"
+#include <stdio.h>
+
+static void clio_write(const char *text) {
+    (void)fputs(text, 1);
+}
+
+static void clio_writeln(const char *text) {
+    (void)fputs(text, 1);
+    (void)putchar('\n');
+}
+
+static void clio_write_char(char ch) {
+    (void)putchar((unsigned char)ch);
+}
+
+static void clio_write_hex_u64(u64 value) {
+    (void)printf("0X%llX", (unsigned long long)value);
+}
+
 static int ush_ls_join_path(const char *dir_path, const char *name, char *out_path, u64 out_size) {
     u64 p = 0ULL;
     u64 i;
@@ -80,30 +99,30 @@ static int ush_ls_is_dot_entry(const char *name) {
 
 static void ush_ls_print_one(const char *name, u64 type, u64 size, int long_mode) {
     if (long_mode == 0) {
-        ush_writeln(name);
+        clio_writeln(name);
         return;
     }
 
     if (type == 2ULL) {
-        ush_write("d ");
+        clio_write("d ");
     } else if (type == 1ULL) {
-        ush_write("f ");
+        clio_write("f ");
     } else {
-        ush_write("? ");
+        clio_write("? ");
     }
 
-    ush_write(name);
+    clio_write(name);
 
     if (type == 1ULL) {
-        ush_write("  size=");
-        ush_write_hex_u64(size);
+        clio_write("  size=");
+        clio_write_hex_u64(size);
     } else if (type == 2ULL) {
-        ush_write("  <DIR>");
+        clio_write("  <DIR>");
     } else {
-        ush_write("  <UNKNOWN>");
+        clio_write("  <UNKNOWN>");
     }
 
-    ush_write_char('\n');
+    clio_write_char('\n');
 }
 
 static int ush_ls_parse_args(const char *arg,
@@ -186,19 +205,19 @@ static int ush_ls_dir(const char *path,
     u64 i;
 
     if (depth > 16ULL) {
-        ush_writeln("ls: recursion depth limit reached");
+        clio_writeln("ls: recursion depth limit reached");
         return 0;
     }
 
     count = cleonos_sys_fs_child_count(path);
 
     if (print_header != 0) {
-        ush_write(path);
-        ush_writeln(":");
+        clio_write(path);
+        clio_writeln(":");
     }
 
     if (count == 0ULL) {
-        ush_writeln("(empty)");
+        clio_writeln("(empty)");
     }
 
     for (i = 0ULL; i < count; i++) {
@@ -249,7 +268,7 @@ static int ush_ls_dir(const char *path,
         }
 
         if (cleonos_sys_fs_stat_type(child_path) == 2ULL) {
-            ush_write_char('\n');
+            clio_write_char('\n');
             (void)ush_ls_dir(child_path, long_mode, recursive, 1, depth + 1ULL);
         }
     }
@@ -265,12 +284,12 @@ static int ush_cmd_ls(const ush_state *sh, const char *arg) {
     int recursive;
 
     if (ush_ls_parse_args(arg, &long_mode, &recursive, target, (u64)sizeof(target)) == 0) {
-        ush_writeln("ls: usage ls [-l] [-R] [path]");
+        clio_writeln("ls: usage ls [-l] [-R] [path]");
         return 0;
     }
 
     if (ush_resolve_path(sh, target, path, (u64)sizeof(path)) == 0) {
-        ush_writeln("ls: invalid path");
+        clio_writeln("ls: invalid path");
         return 0;
     }
 
@@ -283,7 +302,7 @@ static int ush_cmd_ls(const ush_state *sh, const char *arg) {
     }
 
     if (type != 2ULL) {
-        ush_writeln("ls: path not found");
+        clio_writeln("ls: path not found");
         return 0;
     }
 

cleonos/c/apps/shell/shell_internal.h

@@ -2,6 +2,10 @@
 #define CLEONOS_USER_SHELL_INTERNAL_H
 
 #include <cleonos_syscall.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
 typedef long long i64;
 

cleonos/c/apps/shell/shell_util.c

@@ -5,106 +5,53 @@ void ush_init_state(ush_state *sh) {
         return;
     }
 
-    sh->line[0] = '\0';
-    sh->line_len = 0ULL;
-    sh->cursor = 0ULL;
-    sh->rendered_len = 0ULL;
+    (void)memset(sh, 0, sizeof(*sh));
 
     ush_copy(sh->cwd, (u64)sizeof(sh->cwd), "/");
-
-    sh->history_count = 0ULL;
     sh->history_nav = -1;
-    sh->nav_saved_line[0] = '\0';
-    sh->nav_saved_len = 0ULL;
-    sh->nav_saved_cursor = 0ULL;
-
-    sh->cmd_total = 0ULL;
-    sh->cmd_ok = 0ULL;
-    sh->cmd_fail = 0ULL;
-    sh->cmd_unknown = 0ULL;
-    sh->exit_requested = 0;
-    sh->exit_code = 0ULL;
 }
 
 u64 ush_strlen(const char *str) {
-    u64 len = 0ULL;
-
-    if (str == (const char *)0) {
-        return 0ULL;
-    }
-
-    while (str[len] != '\0') {
-        len++;
-    }
-
-    return len;
+    return (str == (const char *)0) ? 0ULL : (u64)strlen(str);
 }
 
 int ush_streq(const char *left, const char *right) {
-    u64 i = 0ULL;
-
     if (left == (const char *)0 || right == (const char *)0) {
         return 0;
     }
-
-    while (left[i] != '\0' && right[i] != '\0') {
-        if (left[i] != right[i]) {
-            return 0;
-        }
-        i++;
-    }
-
-    return (left[i] == right[i]) ? 1 : 0;
+    return (strcmp(left, right) == 0) ? 1 : 0;
 }
 
 int ush_is_space(char ch) {
-    return (ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n') ? 1 : 0;
+    return (isspace((unsigned char)ch) != 0) ? 1 : 0;
 }
 
 int ush_is_printable(char ch) {
-    return (ch >= 32 && ch <= 126) ? 1 : 0;
+    return (isprint((unsigned char)ch) != 0) ? 1 : 0;
 }
 
 int ush_has_suffix(const char *name, const char *suffix) {
-    u64 name_len;
-    u64 suffix_len;
-    u64 i;
+    size_t name_len;
+    size_t suffix_len;
 
     if (name == (const char *)0 || suffix == (const char *)0) {
         return 0;
     }
 
-    name_len = ush_strlen(name);
-    suffix_len = ush_strlen(suffix);
+    name_len = strlen(name);
+    suffix_len = strlen(suffix);
 
     if (suffix_len > name_len) {
         return 0;
     }
-
-    for (i = 0ULL; i < suffix_len; i++) {
-        if (name[name_len - suffix_len + i] != suffix[i]) {
-            return 0;
-        }
-    }
-
-    return 1;
+    return (strncmp(name + (name_len - suffix_len), suffix, suffix_len) == 0) ? 1 : 0;
 }
 
 int ush_contains_char(const char *text, char needle) {
-    u64 i = 0ULL;
-
     if (text == (const char *)0) {
         return 0;
     }
-
-    while (text[i] != '\0') {
-        if (text[i] == needle) {
-            return 1;
-        }
-        i++;
-    }
-
-    return 0;
+    return (strchr(text, (int)needle) != (char *)0) ? 1 : 0;
 }
 
 int ush_parse_u64_dec(const char *text, u64 *out_value) {
@@ -118,7 +65,7 @@ int ush_parse_u64_dec(const char *text, u64 *out_value) {
     while (text[i] != '\0') {
         u64 digit;
 
-        if (text[i] < '0' || text[i] > '9') {
+        if (isdigit((unsigned char)text[i]) == 0) {
             return 0;
         }
 
@@ -137,45 +84,34 @@ int ush_parse_u64_dec(const char *text, u64 *out_value) {
 }
 
 void ush_copy(char *dst, u64 dst_size, const char *src) {
-    u64 i = 0ULL;
-
     if (dst == (char *)0 || src == (const char *)0 || dst_size == 0ULL) {
         return;
     }
-
-    while (src[i] != '\0' && i + 1ULL < dst_size) {
-        dst[i] = src[i];
-        i++;
-    }
-
-    dst[i] = '\0';
+    (void)strncpy(dst, src, (size_t)(dst_size - 1ULL));
+    dst[dst_size - 1ULL] = '\0';
 }
 
 void ush_trim_line(char *line) {
-    u64 start = 0ULL;
-    u64 i = 0ULL;
-    u64 len;
+    size_t start = 0U;
+    size_t len;
 
     if (line == (char *)0) {
         return;
     }
 
-    while (line[start] != '\0' && ush_is_space(line[start]) != 0) {
+    while (line[start] != '\0' && isspace((unsigned char)line[start]) != 0) {
         start++;
     }
 
-    if (start > 0ULL) {
-        while (line[start + i] != '\0') {
-            line[i] = line[start + i];
-            i++;
-        }
-        line[i] = '\0';
+    if (start > 0U) {
+        size_t remain = strlen(line + start) + 1U;
+        (void)memmove(line, line + start, remain);
     }
 
-    len = ush_strlen(line);
+    len = strlen(line);
 
-    while (len > 0ULL && ush_is_space(line[len - 1ULL]) != 0) {
-        line[len - 1ULL] = '\0';
+    while (len > 0U && isspace((unsigned char)line[len - 1U]) != 0) {
+        line[len - 1U] = '\0';
         len--;
     }
 }
@@ -231,7 +167,6 @@ static int ush_out_fd_mirror_tty = 1;
 
 static void ush_output_capture_append(const char *text, u64 len) {
     u64 writable;
-    u64 i;
 
     if (ush_out_capture_active == 0 || text == (const char *)0 || len == 0ULL) {
         return;
@@ -254,9 +189,7 @@ static void ush_output_capture_append(const char *text, u64 len) {
         ush_out_capture_truncated = 1;
     }
 
-    for (i = 0ULL; i < len; i++) {
-        ush_out_capture_buffer[ush_out_capture_length + i] = text[i];
-    }
+    (void)memcpy(ush_out_capture_buffer + ush_out_capture_length, text, (size_t)len);
 
     ush_out_capture_length += len;
     ush_out_capture_buffer[ush_out_capture_length] = '\0';
@@ -341,19 +274,7 @@ void ush_write(const char *text) {
     }
 
     if (should_write_tty != 0) {
-        const char *cursor = text;
-        u64 left = len;
-
-        while (left > 0ULL) {
-            u64 wrote = cleonos_sys_fd_write(1ULL, cursor, left);
-
-            if (wrote == 0ULL || wrote == (u64)-1) {
-                break;
-            }
-
-            cursor += wrote;
-            left -= wrote;
-        }
+        (void)fputs(text, 1);
     }
 }
 
@@ -377,7 +298,7 @@ void ush_write_char(char ch) {
     }
 
     if (should_write_tty != 0) {
-        (void)cleonos_sys_fd_write(1ULL, &ch, 1ULL);
+        (void)fputc((int)(unsigned char)ch, 1);
     }
 }
 

cleonos/c/apps/spin_main.c

@@ -1,11 +1,11 @@
-#include <cleonos_syscall.h>
+#include <stdio.h>
 
 int cleonos_app_main(void) {
     static const char banner[] =
         "spin: busy loop started (test Alt+Ctrl+C force stop)\n";
-    volatile u64 noise = 0xC1E0C1E0ULL;
+    volatile unsigned long long noise = 0xC1E0C1E0ULL;
 
-    (void)cleonos_sys_fd_write(1ULL, banner, (u64)(sizeof(banner) - 1U));
+    (void)fputs(banner, 1);
 
     for (;;) {
         noise ^= (noise << 7);

cleonos/c/apps/tail_main.c

@@ -1,4 +1,5 @@
 #include "cmd_runtime.h"
+#include <stdio.h>
 
 static int ush_tail_parse_args(const char *arg, u64 *out_line_count, char *out_file, u64 out_file_size) {
     char first[USH_PATH_MAX];
@@ -69,24 +70,24 @@ static int ush_tail_load_input(const ush_state *sh, const char *file_arg, const
 
     if (file_arg != (const char *)0 && file_arg[0] != '\0') {
         if (ush_resolve_path(sh, file_arg, path, (u64)sizeof(path)) == 0) {
-            ush_writeln("tail: invalid path");
+            (void)puts("tail: invalid path");
             return 0;
         }
 
         if (cleonos_sys_fs_stat_type(path) != 1ULL) {
-            ush_writeln("tail: file not found");
+            (void)puts("tail: file not found");
             return 0;
         }
 
         size = cleonos_sys_fs_stat_size(path);
 
         if (size == (u64)-1) {
-            ush_writeln("tail: failed to stat file");
+            (void)puts("tail: failed to stat file");
             return 0;
         }
 
         if (size > (u64)USH_COPY_MAX) {
-            ush_writeln("tail: file too large for user buffer");
+            (void)puts("tail: file too large for user buffer");
             return 0;
         }
 
@@ -100,7 +101,7 @@ static int ush_tail_load_input(const ush_state *sh, const char *file_arg, const
         got = cleonos_sys_fs_read(path, file_buf, size);
 
         if (got == 0ULL || got != size) {
-            ush_writeln("tail: read failed");
+            (void)puts("tail: read failed");
             return 0;
         }
 
@@ -111,7 +112,7 @@ static int ush_tail_load_input(const ush_state *sh, const char *file_arg, const
     }
 
     if (ush_pipeline_stdin_text == (const char *)0) {
-        ush_writeln("tail: file path required (or pipeline input)");
+        (void)puts("tail: file path required (or pipeline input)");
         return 0;
     }
 
@@ -174,7 +175,7 @@ static int ush_cmd_tail(const ush_state *sh, const char *arg) {
     }
 
     if (ush_tail_parse_args(arg, &line_count, file_arg, (u64)sizeof(file_arg)) == 0) {
-        ush_writeln("tail: usage tail [-n N] [file]");
+        (void)puts("tail: usage tail [-n N] [file]");
         return 0;
     }
 
@@ -191,7 +192,7 @@ static int ush_cmd_tail(const ush_state *sh, const char *arg) {
     start_offset = ush_tail_find_start_offset(input, input_len, skip_lines);
 
     for (i = start_offset; i < input_len; i++) {
-        ush_write_char(input[i]);
+        (void)putchar((unsigned char)input[i]);
     }
 
     return 1;

cleonos/c/apps/wc_main.c

@@ -1,11 +1,12 @@
 #include "cmd_runtime.h"
+#include <stdio.h>
 
 static void ush_wc_write_u64_dec(u64 value) {
     char tmp[32];
     u64 len = 0ULL;
 
     if (value == 0ULL) {
-        ush_write_char('0');
+        (void)putchar('0');
         return;
     }
 
@@ -16,7 +17,7 @@ static void ush_wc_write_u64_dec(u64 value) {
 
     while (len > 0ULL) {
         len--;
-        ush_write_char(tmp[len]);
+        (void)putchar((unsigned char)tmp[len]);
     }
 }
 
@@ -61,24 +62,24 @@ static int ush_wc_load_input(const ush_state *sh, const char *file_arg, const ch
 
     if (file_arg != (const char *)0 && file_arg[0] != '\0') {
         if (ush_resolve_path(sh, file_arg, path, (u64)sizeof(path)) == 0) {
-            ush_writeln("wc: invalid path");
+            (void)puts("wc: invalid path");
             return 0;
         }
 
         if (cleonos_sys_fs_stat_type(path) != 1ULL) {
-            ush_writeln("wc: file not found");
+            (void)puts("wc: file not found");
             return 0;
         }
 
         size = cleonos_sys_fs_stat_size(path);
 
         if (size == (u64)-1) {
-            ush_writeln("wc: failed to stat file");
+            (void)puts("wc: failed to stat file");
             return 0;
         }
 
         if (size > (u64)USH_COPY_MAX) {
-            ush_writeln("wc: file too large for user buffer");
+            (void)puts("wc: file too large for user buffer");
             return 0;
         }
 
@@ -92,7 +93,7 @@ static int ush_wc_load_input(const ush_state *sh, const char *file_arg, const ch
         got = cleonos_sys_fs_read(path, file_buf, size);
 
         if (got == 0ULL || got != size) {
-            ush_writeln("wc: read failed");
+            (void)puts("wc: read failed");
             return 0;
         }
 
@@ -103,7 +104,7 @@ static int ush_wc_load_input(const ush_state *sh, const char *file_arg, const ch
     }
 
     if (ush_pipeline_stdin_text == (const char *)0) {
-        ush_writeln("wc: file path required (or pipeline input)");
+        (void)puts("wc: file path required (or pipeline input)");
         return 0;
     }
 
@@ -127,7 +128,7 @@ static int ush_cmd_wc(const ush_state *sh, const char *arg) {
     }
 
     if (ush_wc_parse_args(arg, file_arg, (u64)sizeof(file_arg)) == 0) {
-        ush_writeln("wc: usage wc [file]");
+        (void)puts("wc: usage wc [file]");
         return 0;
     }
 
@@ -153,11 +154,11 @@ static int ush_cmd_wc(const ush_state *sh, const char *arg) {
     }
 
     ush_wc_write_u64_dec(lines);
-    ush_write(" ");
+    (void)putchar(' ');
     ush_wc_write_u64_dec(words);
-    ush_write(" ");
+    (void)putchar(' ');
     ush_wc_write_u64_dec(bytes);
-    ush_write_char('\n');
+    (void)putchar('\n');
 
     return 1;
 }