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#include <bool.h>
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#include <bool.h>
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#include <futex.h>
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#include <futex.h>
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#include <libadt/list.h>
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#include <libadt/list.h>
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#include "vfs.h"
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#include "vfs.h"
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- 
 
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#define min(a, b)   ((a) < (b) ? (a) : (b))
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atomic_t plb_futex = FUTEX_INITIALIZER;
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atomic_t plb_futex = FUTEX_INITIALIZER;
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link_t plb_head;
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link_t plb_head;    /**< PLB entry ring buffer. */
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uint8_t *plb = NULL;
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uint8_t *plb = NULL;
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void vfs_lookup(ipc_callid_t rid, ipc_call_t *request)
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int vfs_lookup_internal(char *path, size_t len, vfs_node_t *result)
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{
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{
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    if (!len)
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        return EINVAL;
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    if (!rootfs)
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    if (!rootfs)
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        return ENOENT;
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    futex_down(&plb_futex);
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    plb_entry_t entry;
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    link_initialize(&entry.plb_link);
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    entry.len = len;
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    off_t first;    /* the first free index */
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    off_t last; /* the last free index */
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    if (list_empty(&plb_head)) {
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        first = 0;
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        last = PLB_SIZE - 1;
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    } else {
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        plb_entry_t *oldest = list_get_instance(plb_head.next,
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            plb_entry_t, plb_link);
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        plb_entry_t *newest = list_get_instance(plb_head.prev,
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            plb_entry_t, plb_link);
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        first = (newest->index + newest->len) % PLB_SIZE;
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        last = (oldest->index - 1) % PLB_SIZE;
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    }
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    if (first <= last) {
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        if ((last - first) + 1 < len) {
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            /*
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             * The buffer cannot absorb the path.
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             */
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            futex_up(&plb_futex);
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            return ELIMIT;
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        }
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    } else {
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        if (PLB_SIZE - ((first - last) + 1) < len) {
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            /*
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             * The buffer cannot absorb the path.
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             */
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            futex_up(&plb_futex);
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            return ELIMIT;
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        }
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    }
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    /*
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     * We know the first free index in PLB and we also know that there is
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     * enough space in the buffer to hold our path.
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     */
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    entry.index = first;
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    entry.len = len;
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    /*
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     * Claim PLB space by inserting the entry into the PLB entry ring
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     * buffer.
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     */
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    list_append(&entry.plb_link, &plb_head);
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    futex_up(&plb_futex);
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    /*
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     * Copy the path into PLB.
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     */
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    size_t cnt1 = min(len, (PLB_SIZE - first) + 1);
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    size_t cnt2 = len - cnt1;
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        ipc_answer_fast(rid, ENOENT, 0, 0);
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    memcpy(&plb[first], path, cnt1);
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    memcpy(plb, &path[cnt1], cnt2);
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    ipc_call_t answer;
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    int phone = 0;      /* TODO */
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    aid_t req = async_send_2(phone, VFS_LOOKUP, (ipcarg_t) first,
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        (ipcarg_t) last, &answer);
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    ipcarg_t rc;
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    async_wait_for(req, &rc);
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    futex_down(&plb_futex);
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    list_remove(&entry.plb_link);
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    futex_up(&plb_futex);
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    if (rc == EOK) {
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        result->fs_handle = (int) IPC_GET_ARG1(answer);
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        result->dev_handle = (int) IPC_GET_ARG2(answer);
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        result->index = (int) IPC_GET_ARG3(answer);
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 143 
    }
- 
 
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    return rc;
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}
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}
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/**
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/**
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 * @}
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 * @}
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 */
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 */