r/src/bash_executor.c

// retoor <retoor@molodetz.nl>

#define _GNU_SOURCE
#include "bash_executor.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>

char *r_bash_execute(const char *command, bool interactive) {
    if (!command) {
        return strdup("Error: null command");
    }

    size_t len = strlen(command);
    char *cmd_with_nl = malloc(len + 2);
    if (!cmd_with_nl) {
        return strdup("Error: memory allocation failed");
    }

    strcpy(cmd_with_nl, command);
    if (len > 0 && cmd_with_nl[len - 1] != '\n') {
        cmd_with_nl[len] = '\n';
        cmd_with_nl[len + 1] = '\0';
    } else if (len == 0) {
        cmd_with_nl[0] = '\n';
        cmd_with_nl[1] = '\0';
    }

    char tmp_script[] = "/tmp/r_bash_XXXXXX.sh";
    int fd = mkstemps(tmp_script, 3);
    if (fd == -1) {
        free(cmd_with_nl);
        perror("mkstemps");
        return strdup("Error: failed to create temp script");
    }

    if (write(fd, cmd_with_nl, strlen(cmd_with_nl)) == -1) {
        close(fd);
        free(cmd_with_nl);
        unlink(tmp_script);
        return strdup("Error: failed to write to temp script");
    }
    
    close(fd);
    free(cmd_with_nl);

    char *output = NULL;

    if (interactive) {
        char *run_cmd = NULL;
        if (asprintf(&run_cmd, "bash %s", tmp_script) == -1) {
            unlink(tmp_script);
            return strdup("Error: asprintf failed");
        }
        int status = system(run_cmd);
        free(run_cmd);

        if (asprintf(&output, "Command exited with status %d", status) == -1) {
            output = strdup("Command completed (asprintf failed for status).");
        }
    } else {
        char *run_cmd = NULL;
        if (asprintf(&run_cmd, "bash %s 2>&1", tmp_script) == -1) {
            unlink(tmp_script);
            return strdup("Error: asprintf failed");
        }
        
        FILE *fp = popen(run_cmd, "r");
        free(run_cmd);

        if (!fp) {
            unlink(tmp_script);
            return strdup("Error: popen failed");
        }

        char buffer[1024];
        size_t total_size = 0;

        while (fgets(buffer, sizeof(buffer), fp)) {
            // Print to stderr for the user in a subtle dim/gray color
            fprintf(stderr, "\033[2m%s\033[0m", buffer);
            
            size_t chunk_len = strlen(buffer);
            char *new_output = realloc(output, total_size + chunk_len + 1);
            if (!new_output) {
                free(output);
                pclose(fp);
                unlink(tmp_script);
                return strdup("Error: memory allocation failed");
            }
            output = new_output;
            strcpy(output + total_size, buffer);
            total_size += chunk_len;
        }
        pclose(fp);

        if (!output) {
            output = strdup("");
        }
    }

    unlink(tmp_script);
    return output;
}