codecrafters-shell-c

commit c83d3ad2215baa5da4309224a33cdb9d7029a2d8
parent 9d332950dd77f13f48c8bff595208b70c1139d9d
Author: 5hif7y <[email protected]>
Date:   Fri,  3 Jan 2025 01:44:20 -0300

9 run a program

Diffstat:
M
app/main.c
 | 
101
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---------

1 file changed, 90 insertions(+), 11 deletions(-)
diff --git a/app/main.c b/app/main.c
@@ -4,13 +4,17 @@
 #include <stdlib.h>
 
 #ifdef _WIN32
+  #define WIN32_LEAN_AND_MEAN
+  #include <windows.h>
   #define F_OK 0
 #else
+  #include <sys/wait.h>
   #include <unistd.h>
 #endif
 
 void parse_input(const char *input, char *cmd, char **args, int *argc);
 bool find_executable(const char *cmd, char *result_path);
+void run_executable(const char *cmd, char **args);
 
 int main() {
 
@@ -65,7 +69,12 @@ int main() {
 	  printf("Usage: type [command]\n");
 	}
       } else {
-        printf("%s: command not found\n", cmd);
+	char path[512];
+	if (find_executable(cmd, path)){
+	  run_executable(path, args);
+	} else {
+          printf("%s: command not found\n", cmd);
+	}
       }
 
     //free mem
@@ -101,6 +110,33 @@ void parse_input(const char *input, char *cmd, char **args, int *argc){
 }
 
 bool find_executable(const char *cmd, char *result_path){
+
+  // First, search in current folder
+  #ifdef _WIN32
+    const char *extensions[] = {".exe", NULL}; // Extension support list
+    // ------------
+    if (strchr(cmd, '.')){
+      snprintf(result_path, 512, ".\\%s", cmd);
+      if (access(result_path, F_OK) == 0){
+        return true;
+      }
+    } else {
+      for (const char **ext = extensions; *ext != NULL; ext++){
+        snprintf(result_path, 512, ".\\%s%s", cmd, *ext);
+        if (access(result_path, F_OK) == 0){
+          return true;
+        }
+      }
+
+  #else
+    // In POSIX systems, simply search in current folder
+    snprintf(result_path, 512, "./%s", cmd);
+    if (access(result_path, F_OK) == 0){
+      return true;
+    }
+  #endif
+
+  // Second, search in PATH
   char *path_env = getenv("PATH");
   if(!path_env){
     return false;
@@ -111,32 +147,75 @@ bool find_executable(const char *cmd, char *result_path){
   path_copy[sizeof(path_copy) - 1] = '\0';
 
   char separator = ':';
-#ifdef _WIN32
-  separator = ';';
-#endif
+  #ifdef _WIN32
+    separator = ';';
+  #endif
 
   char *dir = strtok(path_copy, &separator);
   while (dir != NULL){
-    snprintf(result_path, 512, "%s/%s", dir, cmd);
-#ifdef _WIN32
-    const char *extensions[] = {".exe", NULL}; // Extension support list
-    for (const char **ext = extensions; *ext != NULL; ext++){
-      snprintf(result_path, 512, "%s\\%s%s", dir, cmd, *ext);
+    if (strlen(dir) > 0) {
+  #ifdef _WIN32
+    if (strchr(cmd, '.')){
+      snprintf(result_path, 512, "%s\\%s", dir, cmd);
       if (access(result_path, F_OK) == 0){
         return true;
       }
+    } else {
+      for (const char **ext = extensions; *ext != NULL; ext++){
+        snprintf(result_path, 512, "%s\\%s%s", dir, cmd, *ext);
+        if (access(result_path, F_OK) == 0){
+          return true;
+        }
+      }
     }
-#else
+  #else
+    snprintf(result_path, 512, "%s/%s", dir, cmd);
     if(access(result_path, X_OK) == 0){
       return true;
     }
-#endif
+  #endif
+    }
     dir = strtok(NULL, &separator);
   }
 
   return false;
 }
 
+void run_executable(const char *cmd, char **args){
+  #ifdef _WIN32
+  // 1. Build command line
+  char command_line[1024] = {0};
+  snprintf(command_line, sizeof(command_line), "\"%s\"", cmd);
+
+  for (int i = 0; args[i] != NULL; i++){
+    strncat(command_line, " ", sizeof(command_line) - strlen(command_line) - 1);
+    strncat(command_line, args[i], sizeof(command_line) - strlen(command_line) - 1);
+  }
 
+  // 2. Setup structures for 'CreateProcess'
+  STARTUPINFO si = {0};
+  PROCESS_INFORMATION pi = {0};
+  si.cb = sizeof(STARTUPINFO);
+
+  // 3. Try to create process
+  if (!CreateProcess(NULL, command_line, NULL, NULL, FALSE, 0, NULL, NULL, &si, &pi)){
+    fprintf(stderr, "Error: error executing command %s\n", cmd);
+  } else {
+    WaitForSingleObject(pi.hProcess, INFINITE);
+    CloseHandle(pi.hProcess);
+    CloseHandle(pi.hThread);
+  }
+
+  #else
+    // Use 'execvp' in POSIX systems
+    if (fork() == 0){
+      execvp(cmd, args);
+      perror("Error executing command");
+      exit(EXIT_FAILURE);
+    } else {
+      wait(NULL);
+    }
+  #endif
+}