find finished

user/find.c

@@ -1,12 +1,64 @@
-#include "kernel/fcntl.h"
 #include "kernel/fs.h"
 #include "kernel/stat.h"
 #include "kernel/types.h"
 #include "user/user.h"
 
-int main(int argc, char *argv[]) {
-  if (argc < 3) {
-    printf("Usage: find path pattern\n");
+void find(char *path, char *filename) {
+  int fd = open(path, 0);
+  char buf[512], *p;
+  struct dirent de;
+  struct stat st;
+
+  if (fd < 0 || strlen(path) + 1 + DIRSIZ + 1 >= sizeof(buf)) {
+    fprintf(2, "find: Invalid path: %s\n", path);
+    // close(fd);
+    return;
   }
+
+  if (fstat(fd, &st) < 0) {
+    fprintf(2, "find: Failed to stat %s\n", path);
+    close(fd);
+    return;
+  }
+
+  if (st.type != T_DIR) {
+    fprintf(2, "find: %s is not a directory\n", path);
+    close(fd);
+    return;
+  }
+
+  strncpy(buf, path, strlen(path) + 1);
+  p = buf + strlen(path);
+  *p++ = '/';
+  while (read(fd, &de, sizeof(de)) == sizeof(de)) {
+    if (de.inum == 0)
+      continue;
+    if (!strcmp(de.name, ".") || !strcmp(de.name, ".."))
+      continue;
+
+    memmove(p, de.name, DIRSIZ);
+    p[DIRSIZ] = 0;
+
+    if (stat(buf, &st) < 0) {
+      fprintf(2, "find: Failed to stat %s\n", buf);
+      continue;
+    }
+
+    if (st.type == T_DIR) {
+      find(buf, filename);
+    } else if (st.type == T_FILE) {
+      if (!strcmp(filename, "*") || !strcmp(filename, de.name)) {
+        printf("%s\n", buf);
+      }
+    }
+  }
+}
+
+int main(int argc, char *argv[]) {
+  if (argc != 3) {
+    printf("Usage: find path filename\n");
+    exit(1);
+  }
+  find(argv[1], argv[2]);
   exit(0);
 }

user/ulib.c

@@ -21,12 +21,33 @@ char *strcpy(char *s, const char *t) {
   return os;
 }
 
+char *strncpy(char *s, const char *t, int n) {
+  char *os;
+
+  os = s;
+  if (n <= 0)
+    return os;
+  while (--n > 0 && (*s++ = *t++) != 0)
+    ;
+  while (n-- > 0)
+    *s++ = 0;
+  return os;
+}
+
 int strcmp(const char *p, const char *q) {
   while (*p && *p == *q)
     p++, q++;
   return (uchar)*p - (uchar)*q;
 }
 
+int strncmp(const char *p, const char *q, int n) {
+  while (n > 0 && *p && *p == *q)
+    p++, q++, n--;
+  if (n == 0)
+    return 0;
+  return (uchar)*p - (uchar)*q;
+}
+
 uint strlen(const char *s) {
   int n;
 

user/user.h

@@ -27,9 +27,11 @@ int uptime(void);
 // ulib.c
 int stat(const char *, struct stat *);
 char *strcpy(char *, const char *);
+char *strncpy(char *, const char *, int);
 void *memmove(void *, const void *, int);
 char *strchr(const char *, char c);
 int strcmp(const char *, const char *);
+int strncmp(const char *, const char *, int);
 void fprintf(int, const char *, ...);
 void printf(const char *, ...);
 char *gets(char *, int max);