first commit

1 files changed, 238 insertions, 0 deletions

diff --git a/xcwd.c b/xcwd.c
new file mode 100644
index 0000000..e5cb4fb
--- /dev/null
+++ b/xcwd.c
@@ -0,0 +1,238 @@
+/* This is fcwd written by Adrien Schildknecht (c) 2013
+ * Email: adrien+dev@schischi.me
+ * Feel free to copy and redistribute in terms of the
+ * BSD license
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <glob.h>
+#include <sys/stat.h>
+#include <X11/Xlib.h>
+
+#define XA_STRING (XInternAtom(dpy, "STRING", 0))
+
+Display *dpy;
+
+typedef struct processes_s *processes_t;
+struct processes_s {
+    struct proc_s {
+        long pid;
+        long ppid;
+        char name[32];
+    } *ps;
+    size_t n;
+};
+
+int nameCmp(const void *p1, const void *p2)
+{
+    return strcasecmp(((struct proc_s *)p1)->name,
+            ((struct proc_s *)p2)->name);
+}
+
+int ppidCmp(const void *p1, const void *p2)
+{
+    return ((struct proc_s *)p1)->ppid - ((struct proc_s *)p2)->ppid;
+}
+
+static Window focusedWindow()
+{
+    Window focuswin;
+    int focusrevert;
+
+    dpy = XOpenDisplay (NULL);
+    if (!dpy)
+        exit (1);
+    XGetInputFocus (dpy, &focuswin, &focusrevert);
+#ifdef DEBUG
+    fprintf(stderr, "Window ID = %lu\n", focuswin);
+#endif
+    return focuswin;
+}
+
+static long windowPid(Window focuswin)
+{
+    Atom nameAtom = XInternAtom(dpy, "_NET_WM_PID", 1);
+    Atom cardinalAtom = XInternAtom(dpy, "CARDINAL", 0);
+    Atom type;
+    int format;
+    long pid = -1;
+    unsigned long nitems, after;
+    unsigned char *data = 0;
+
+    if (XGetWindowProperty(dpy, focuswin, nameAtom, 0, 1024, 0, cardinalAtom,
+                &type, &format, &nitems, &after, &data) == Success) {
+        if (data) {
+            pid = *((long*)data);
+            XFree(data);
+        }
+    }
+#ifdef DEBUG
+    if(pid == -1)
+        fprintf(stderr, "_NET_WM_PID not found\n");
+    else
+        fprintf(stderr, "_NET_WM_PID = %lu\n", pid);
+#endif
+    return pid;
+}
+
+static char* windowStrings(Window focuswin, size_t *size, char* hint)
+{
+    Atom nameAtom = XInternAtom(dpy, hint, 1);
+    Atom type;
+    int format;
+    int i;
+    unsigned long after;
+    unsigned char *data = 0;
+    char *ret = NULL;
+
+    if (XGetWindowProperty(dpy, focuswin, nameAtom, 0, 1024, 0, AnyPropertyType,
+                &type, &format, size, &after, &data) == Success) {
+        if (data) {
+            if(type == XA_STRING) {
+                ret = malloc(sizeof(char) * *size);
+#ifdef DEBUG
+                fprintf(stderr, "%s = ", hint);
+#endif
+                for(i = 0; i < *size; ++i) {
+#ifdef DEBUG
+                    fprintf(stderr, "%c", data[i] == 0 ? ' ' : data[i]);
+#endif
+                    ret[i] = data[i];
+                }
+#ifdef DEBUG
+                    fprintf(stderr, "\n");
+#endif
+            }
+            XFree(data);
+        }
+#ifdef DEBUG
+        else
+            fprintf(stderr, "%s not found\n", hint);
+#endif
+    }
+    return ret;
+}
+
+static void freeProcesses(processes_t p)
+{
+    free(p->ps);
+    free(p);
+}
+
+static processes_t getProcesses(void)
+{
+    glob_t globbuf;
+    unsigned int i, j;
+    processes_t p;
+
+    glob("/proc/[0-9]*", GLOB_NOSORT, NULL, &globbuf);
+    p = malloc(sizeof(struct processes_s));
+    p->ps = malloc(globbuf.gl_pathc * sizeof(struct proc_s));
+
+#ifdef DEBUG
+        fprintf(stderr, "Found %ld processes\n", globbuf.gl_pathc);
+#endif
+    for (i = j = 0; i < globbuf.gl_pathc; i++) {
+        char name[32];
+        FILE *tn;
+
+        (void)globbuf.gl_pathv[globbuf.gl_pathc - i - 1];
+        snprintf(name, sizeof(name), "%s%s",
+                globbuf.gl_pathv[globbuf.gl_pathc - i - 1], "/stat");
+        tn = fopen(name, "r");
+        if (tn == NULL)
+            continue;
+        fscanf(tn, "%ld (%32[^)] %*3c %ld", &p->ps[j].pid, p->ps[j].name,
+                &p->ps[j].ppid);
+#ifdef DEBUG
+        fprintf(stderr, "\t%-20s\tpid=%6ld\tppid=%6ld\n", p->ps[j].name,
+                p->ps[j].pid, p->ps[j].ppid);
+#endif
+        fclose(tn);
+        j++;
+    }
+    p->n = j;
+    globfree(&globbuf);
+    return p;
+}
+
+static long lastChild(processes_t p, long pid)
+{
+    struct proc_s key, *res;
+
+    do {
+        key.ppid = pid;
+        res = (struct proc_s *)bsearch(&key, p->ps, p->n,
+                sizeof(struct proc_s), ppidCmp);
+        pid = res ? res->pid : -1;
+    }while(pid != -1);
+    return key.ppid;
+}
+
+static void readPath(long pid)
+{
+    char buf[255];
+    char path[64];
+    snprintf(path, sizeof(path), "/proc/%ld/cwd", pid);
+#ifdef DEBUG
+    fprintf(stderr, "Read %s\n", path);
+#endif
+    readlink(path, buf, 255);
+    fprintf(stdout, "%s\n", buf);
+}
+
+int main(int argc, const char *argv[])
+{
+    processes_t p;
+    Window w = focusedWindow();
+    long pid;
+
+    pid = windowPid(w);
+    p = getProcesses();
+    if(pid != -1) { // WM_NET_PID
+        qsort(p->ps, p->n, sizeof(struct proc_s), ppidCmp);
+    }
+    else {
+        size_t size;
+        char* strings;
+        int i;
+        struct proc_s *res = NULL, key;
+        qsort(p->ps, p->n, sizeof(struct proc_s), nameCmp);
+        strings = windowStrings(w, &size, "WM_CLASS");
+        for(i = 0; i < size; i += strlen(strings + i) + 1) {
+#ifdef DEBUG
+            fprintf(stderr, "pidof %s\n", strings + i);
+#endif
+            strcpy(key.name, strings + i);
+            res = (struct proc_s *)bsearch(&key, p->ps, p->n,
+                sizeof(struct proc_s), nameCmp);
+            if(res)
+                break;
+        }
+        if(res) {
+            pid = res->pid;
+#ifdef DEBUG
+            fprintf(stderr, "Found %s (%ld)\n", res->name, res->pid);
+#endif
+        }
+        if(size != 0)
+            free(strings);
+    }
+    if(pid != -1) {
+        pid = lastChild(p, pid);
+        readPath(pid);
+    }
+    else {
+#ifdef DEBUG
+        fprintf(stderr, "getenv $HOME...\n");
+#endif
+        fprintf(stdout, "%s\n", getenv("HOME"));
+    }
+    freeProcesses(p);
+
+    return EXIT_SUCCESS;
+}
+