1 files changed, 150 insertions, 0 deletions
diff --git a/src/platform/freedesktop/desktop.c b/src/platform/freedesktop/desktop.c
new file mode 100644
index 0000000..a8b9bc7
--- /dev/null
+++ b/src/platform/freedesktop/desktop.c
@@ -0,0 +1,150 @@
+#define _GNU_SOURCE
+#include "common/desktop.h"
+#include "platform/freedesktop/dbus.h"
+#include "yasl/desktop.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/syscall.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+extern char **environ;
+
+static size_t copy_str(char *buf, size_t cap, const char *s)
+{
+    size_t len = strlen(s);
+    if (!len || len >= cap) return 0;
+    memcpy(buf, s, len + 1);
+    return len;
+}
+
+/* Find an executable in PATH, like execvp but before forking. */
+static bool find_program(const char *name, char *out, size_t cap)
+{
+    const char *path = getenv("PATH");
+    if (!path || !*path) path = "/usr/local/bin:/usr/bin:/bin";
+    size_t name_len = strlen(name);
+    while (*path) {
+        const char *end = strchr(path, ':');
+        size_t dir_len = end ? (size_t)(end - path) : strlen(path);
+        if (dir_len && dir_len + 1 + name_len < cap) {
+            memcpy(out, path, dir_len);
+            out[dir_len] = '/';
+            memcpy(out + dir_len + 1, name, name_len + 1);
+            if (access(out, X_OK) == 0) return true;
+        }
+        if (!end) break;
+        path = end + 1;
+    }
+    return false;
+}
+
+bool desktop_open_uri(const char *uri)
+{
+    char program[4096];
+    if (!find_program("xdg-open", program, sizeof(program))) return false;
+    char *argv[] = {"xdg-open", (char *)uri, NULL};
+
+    /* Prepare everything before fork: the children of a threaded process may
+     * only make async-signal-safe calls. */
+    struct sigaction dfl = {.sa_handler = SIG_DFL};
+    sigemptyset(&dfl.sa_mask);
+    sigset_t none;
+    sigemptyset(&none);
+    long max_fd = sysconf(_SC_OPEN_MAX);
+    if (max_fd < 0 || max_fd > 65536) max_fd = 65536;
+
+    /* The middle child exits at once, so the opener is reparented away from
+     * the application and never needs reaping here. */
+    pid_t pid = fork();
+    if (pid < 0) return false;
+    if (pid == 0) {
+        setsid();
+        pid_t opener = fork();
+        if (opener != 0) _exit(opener < 0 ? 1 : 0);
+        for (int sig = 1; sig < NSIG; sig++)
+            if (sig != SIGKILL && sig != SIGSTOP) sigaction(sig, &dfl, NULL);
+        sigprocmask(SIG_SETMASK, &none, NULL);
+        int null = open("/dev/null", O_RDONLY);
+        if (null > 0) {
+            dup2(null, STDIN_FILENO);
+            close(null);
+        }
+        /* Keep application descriptors, such as pty masters, out of the opener. */
+#ifdef SYS_close_range
+        if (syscall(SYS_close_range, 3u, ~0u, 0u) != 0)
+#endif
+            for (int fd = 3; fd < max_fd; fd++) close(fd);
+        execve(program, argv, environ);
+        _exit(127);
+    }
+
+    int status;
+    pid_t done;
+    do {
+        done = waitpid(pid, &status, 0);
+    } while (done < 0 && errno == EINTR);
+    /* An application reaper can collect the middle child first. */
+    if (done < 0) return errno == ECHILD;
+    return WIFEXITED(status) && WEXITSTATUS(status) == 0;
+}
+
+bool desktop_notify(const char *app_id, const char *title, const char *body)
+{
+    return bus_notify(app_id ? app_id : "yasl", title, body);
+}
+
+uint32_t desktop_appearance(void)
+{
+    uint32_t flags = 0;
+    bool portal = false;
+    int64_t value;
+    if (portal_read_int("org.freedesktop.appearance", "color-scheme", &value)) {
+        portal = true;
+        if (value == 1) flags |= YASL_APPEARANCE_DARK;
+        else if (value == 2) flags |= YASL_APPEARANCE_LIGHT;
+    }
+    if (portal_read_int("org.freedesktop.appearance", "contrast", &value)) {
+        portal = true;
+        if (value == 1) flags |= YASL_APPEARANCE_HIGH_CONTRAST;
+    }
+    if (portal) return flags;
+
+    /* GTK_THEME is "Name" or "Name:variant", as in "Adwaita:dark". */
+    const char *theme = getenv("GTK_THEME");
+    if (!theme) return 0;
+    if (strstr(theme, "HighContrast")) flags |= YASL_APPEARANCE_HIGH_CONTRAST;
+    if (strstr(theme, ":dark") || strstr(theme, "HighContrastInverse"))
+        flags |= YASL_APPEARANCE_DARK;
+    return flags;
+}
+
+size_t desktop_executable_path(char *buf, size_t cap)
+{
+    /* readlink truncates silently, so a full buffer may hold a cut path. */
+    ssize_t len = readlink("/proc/self/exe", buf, cap);
+    if (len <= 0 || (size_t)len >= cap) return 0;
+    buf[len] = '\0';
+    return (size_t)len;
+}
+
+size_t desktop_resource_dir(char *buf, size_t cap)
+{
+    (void)buf;
+    (void)cap;
+    return 0;
+}
+
+size_t desktop_default_locale(char *buf, size_t cap)
+{
+    static const char *const vars[] = {"LC_ALL", "LC_CTYPE", "LANG"};
+    for (size_t i = 0; i < sizeof(vars) / sizeof(vars[0]); i++) {
+        const char *v = getenv(vars[i]);
+        if (v && *v) return copy_str(buf, cap, v);
+    }
+    return copy_str(buf, cap, "C.UTF-8");
+}