Current_files_prop.thy
changeset 1 7d9c0ed02b56
child 2 5a01ee1c9b4d
equal deleted inserted replaced
0:34d01e9a772e 1:7d9c0ed02b56
       
     1 (*<*)
       
     2 theory Current_files_prop
       
     3 imports Main Flask_type Flask My_list_prefix Init_prop Valid_prop
       
     4 begin
       
     5 (*<*)
       
     6 
       
     7 context init begin
       
     8 
       
     9 lemma current_files_ndef: "f \<notin> current_files \<tau> \<Longrightarrow> inum_of_file \<tau> f = None"
       
    10 by (simp add:current_files_def)
       
    11 
       
    12 (************** file_of_proc_fd vs proc_fd_of_file *****************)
       
    13 lemma pfdof_simp1: "file_of_proc_fd \<tau> p fd = Some f \<Longrightarrow> (p, fd) \<in> proc_fd_of_file \<tau> f"
       
    14 by (simp add:proc_fd_of_file_def)
       
    15 
       
    16 lemma pfdof_simp2: "(p, fd) \<in> proc_fd_of_file \<tau> f \<Longrightarrow> file_of_proc_fd \<tau> p fd = Some f"
       
    17 by (simp add:proc_fd_of_file_def)
       
    18 
       
    19 lemma pfdof_simp3: "proc_fd_of_file \<tau> f = {(p, fd)} \<Longrightarrow> \<forall> p' fd'. (file_of_proc_fd \<tau> p' fd' = Some f \<longrightarrow> p = p' \<and> fd = fd')"
       
    20 by (simp add:proc_fd_of_file_def, auto)
       
    21 
       
    22 lemma pfdof_simp4: "\<lbrakk>file_of_proc_fd \<tau> p' fd' = Some f; proc_fd_of_file \<tau> f = {(p, fd)}\<rbrakk> \<Longrightarrow> p' = p \<and> fd' = fd"
       
    23 by (drule pfdof_simp3, auto)
       
    24 
       
    25 end
       
    26 
       
    27 context flask begin
       
    28 
       
    29 (***************** inode number lemmas *************************)
       
    30 
       
    31 lemma iof's_im_in_cim: "inum_of_file \<tau> f = Some im \<Longrightarrow> im \<in> current_inode_nums \<tau>"
       
    32 by (auto simp add:current_inode_nums_def current_file_inums_def)
       
    33 
       
    34 lemma ios's_im_in_cim: "inum_of_socket \<tau> s = Some im \<Longrightarrow> im \<in> current_inode_nums \<tau>"
       
    35 by (case_tac s, auto simp add:current_inode_nums_def current_sock_inums_def)
       
    36 
       
    37 lemma fim_noninter_sim_aux[rule_format]:
       
    38   "\<forall> f s. inum_of_file \<tau> f = Some im \<and> inum_of_socket \<tau> s = Some im \<and> valid \<tau> \<longrightarrow> False"
       
    39 apply (induct \<tau>)
       
    40 apply (clarsimp simp:inum_of_file.simps inum_of_socket.simps)
       
    41 apply (drule init_inum_sock_file_noninter, simp, simp)
       
    42 apply ((rule allI|rule impI|erule conjE)+)
       
    43 apply (frule vd_cons, frule vt_grant_os, simp, case_tac a) 
       
    44 apply (auto simp:inum_of_file.simps inum_of_socket.simps split:if_splits option.splits
       
    45             dest:ios's_im_in_cim iof's_im_in_cim)
       
    46 done
       
    47 
       
    48 lemma fim_noninter_sim':"\<lbrakk>inum_of_file \<tau> f = Some im; inum_of_socket \<tau> s = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> False"
       
    49 by (auto intro:fim_noninter_sim_aux)
       
    50 
       
    51 lemma fim_noninter_sim'':"\<lbrakk>inum_of_socket \<tau> s = Some im; inum_of_file \<tau> f = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> False"
       
    52 by (auto intro:fim_noninter_sim_aux)
       
    53 
       
    54 lemma fim_noninter_sim: "valid \<tau> \<Longrightarrow> (current_file_inums \<tau>) \<inter> (current_sock_inums \<tau>) = {}"
       
    55 by (auto simp:current_file_inums_def current_sock_inums_def intro:fim_noninter_sim_aux[rule_format])
       
    56 
       
    57 (******************* file inum has inode tag ************************)
       
    58 
       
    59 lemma finum_has_itag_aux[rule_format]: 
       
    60   "\<forall> f im. inum_of_file \<tau> f = Some im \<and> valid \<tau> \<longrightarrow> itag_of_inum \<tau> im \<noteq> None"
       
    61 apply (induct \<tau>)
       
    62 apply (clarsimp simp:inum_of_file.simps itag_of_inum.simps init_inum_of_file_props)
       
    63 apply (clarify, frule vt_grant_os, frule vd_cons, case_tac a) 
       
    64 apply (auto simp add:inum_of_file.simps itag_of_inum.simps os_grant.simps current_files_def 
       
    65                 dest:fim_noninter_sim'' split:option.splits if_splits t_socket_type.splits)
       
    66 done
       
    67 
       
    68 lemma finum_has_itag: "\<lbrakk>inum_of_file \<tau> f = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> \<exists> tag. itag_of_inum \<tau> im = Some tag"
       
    69 by (auto dest:conjI[THEN finum_has_itag_aux])
       
    70 
       
    71 (*********************** file inum is file itag *************************)
       
    72 
       
    73 lemma finum_has_ftag_aux[rule_format]: 
       
    74   "\<forall> f tag. inum_of_file \<tau> f = Some im \<and> itag_of_inum \<tau> im = Some tag \<and> valid \<tau> \<longrightarrow> is_file_dir_itag tag"
       
    75 apply (induct \<tau>)
       
    76 apply (clarsimp simp:inum_of_file.simps itag_of_inum.simps init_inum_of_file_props)
       
    77 apply (clarify, frule vt_grant_os, frule vd_cons, case_tac a) 
       
    78 apply (auto simp:inum_of_file.simps os_grant.simps current_files_def itag_of_inum.simps 
       
    79            split:if_splits option.splits t_socket_type.splits
       
    80             dest:ios's_im_in_cim iof's_im_in_cim)
       
    81 done
       
    82 
       
    83 lemma finum_has_ftag:
       
    84   "\<lbrakk>inum_of_file \<tau> f = Some im; itag_of_inum \<tau> im = Some tag; valid \<tau>\<rbrakk> \<Longrightarrow> is_file_dir_itag tag"
       
    85 by (auto intro:finum_has_ftag_aux)
       
    86 
       
    87 lemma finum_has_ftag': 
       
    88   "\<lbrakk>inum_of_file \<tau> f = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> itag_of_inum \<tau> im = Some Tag_FILE \<or> itag_of_inum \<tau> im = Some Tag_DIR"
       
    89 apply (frule finum_has_itag, simp, erule exE, drule finum_has_ftag, simp+)
       
    90 apply (case_tac tag, auto)
       
    91 done
       
    92 
       
    93 (******************* sock inum has inode tag ************************)
       
    94 
       
    95 lemma sinum_has_itag_aux[rule_format]: 
       
    96   "\<forall> s im. inum_of_socket \<tau> s = Some im \<and> valid \<tau> \<longrightarrow> itag_of_inum \<tau> im \<noteq> None"
       
    97 apply (induct \<tau>)
       
    98 apply (clarsimp simp:inum_of_socket.simps itag_of_inum.simps)
       
    99 apply (drule init_inumos_prop4, clarsimp)
       
   100 apply (clarify, frule vt_grant_os, frule vd_cons, case_tac a) 
       
   101 apply (auto simp add:inum_of_socket.simps itag_of_inum.simps os_grant.simps 
       
   102                 dest:fim_noninter_sim'' ios's_im_in_cim iof's_im_in_cim
       
   103                split:option.splits if_splits t_socket_type.splits)
       
   104 done
       
   105 
       
   106 lemma sinum_has_itag: "\<lbrakk>inum_of_socket \<tau> s = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> \<exists> tag. itag_of_inum \<tau> im = Some tag"
       
   107 by (auto dest:conjI[THEN sinum_has_itag_aux])
       
   108 
       
   109 (********************** socket inum is socket itag **********************)
       
   110 
       
   111 lemma sinum_has_stag_aux[rule_format]: 
       
   112   "\<forall> s tag. inum_of_socket \<tau> s = Some im \<and> itag_of_inum \<tau> im = Some tag \<and> valid \<tau> \<longrightarrow> is_sock_itag tag"
       
   113 apply (induct \<tau>)
       
   114 apply (clarsimp simp:inum_of_socket.simps itag_of_inum.simps)
       
   115 apply (drule init_inumos_prop4, clarsimp)
       
   116 apply (clarify, frule vt_grant_os, frule vd_cons, case_tac a) 
       
   117 apply (auto simp add:inum_of_socket.simps itag_of_inum.simps os_grant.simps 
       
   118                 dest:fim_noninter_sim'' ios's_im_in_cim iof's_im_in_cim
       
   119                split:option.splits if_splits t_socket_type.splits)
       
   120 done
       
   121 
       
   122 lemma sinum_has_stag: "\<lbrakk>inum_of_socket \<tau> s = Some im; itag_of_inum \<tau> im = Some tag; valid \<tau>\<rbrakk> \<Longrightarrow> is_sock_itag tag"
       
   123 by (auto dest:conjI[THEN sinum_has_stag_aux])
       
   124 
       
   125 lemma sinum_has_stag': 
       
   126   "\<lbrakk>inum_of_socket \<tau> s = Some im; valid \<tau>\<rbrakk> 
       
   127    \<Longrightarrow> itag_of_inum \<tau> im = Some Tag_UDP_SOCK \<or> itag_of_inum \<tau> im = Some Tag_TCP_SOCK"
       
   128 apply (frule sinum_has_itag, simp, erule exE)
       
   129 apply (drule sinum_has_stag, simp+, case_tac tag, simp+)
       
   130 done
       
   131 
       
   132 (************************************ 4 in 1 *************************************)
       
   133 
       
   134 lemma file_leveling: "valid \<tau> \<longrightarrow> (
       
   135                         (\<forall> f. f \<in> files_hung_by_del \<tau> \<longrightarrow> inum_of_file \<tau> f \<noteq> None) \<and>
       
   136                         (\<forall> f pf im. parent f = Some pf \<and> inum_of_file \<tau> f = Some im \<longrightarrow> inum_of_file \<tau> pf \<noteq> None) \<and>
       
   137                         (\<forall> f f' im. is_file \<tau> f \<and> parent f' = Some f \<and> inum_of_file \<tau> f' = Some im \<longrightarrow> False) \<and>
       
   138                         (\<forall> f f' im. f \<in> files_hung_by_del \<tau> \<and> inum_of_file \<tau> f' = Some im \<and> parent f' = Some f \<longrightarrow> False) )"
       
   139 proof (induct \<tau>)
       
   140   case Nil 
       
   141   show ?case
       
   142     apply (auto simp:inum_of_file.simps files_hung_by_del.simps is_file_def itag_of_inum.simps parent_file_in_init split:option.splits t_inode_tag.splits)
       
   143     apply (drule init_files_hung_by_del_props, simp add:init_file_has_inum)
       
   144     apply (rule init_parent_file_has_inum, simp+)
       
   145     apply (rule init_file_has_no_son', simp+)
       
   146     apply (rule init_file_hung_has_no_son, simp+)
       
   147     done   
       
   148 next
       
   149   case (Cons a \<tau>)  
       
   150   assume pre: "valid \<tau> \<longrightarrow>
       
   151   (\<forall> f. f \<in> files_hung_by_del \<tau> \<longrightarrow> inum_of_file \<tau> f \<noteq> None) \<and>
       
   152   (\<forall>f pf im. parent f = Some pf \<and> inum_of_file \<tau> f = Some im \<longrightarrow> inum_of_file \<tau> pf \<noteq> None) \<and>
       
   153   (\<forall>f f' im. is_file \<tau> f \<and> parent f' = Some f \<and> inum_of_file \<tau> f' = Some im \<longrightarrow> False) \<and> 
       
   154   (\<forall>f f' im. f \<in> files_hung_by_del \<tau> \<and> inum_of_file \<tau> f' = Some im \<and> parent f' = Some f \<longrightarrow> False)"
       
   155   show ?case
       
   156   proof 
       
   157     assume cons:"valid (a # \<tau>)"
       
   158     show "(\<forall>f. f \<in> files_hung_by_del (a # \<tau>) \<longrightarrow> inum_of_file (a # \<tau>) f \<noteq> None) \<and>
       
   159           (\<forall>f pf im. parent f = Some pf \<and> inum_of_file (a # \<tau>) f = Some im \<longrightarrow> inum_of_file (a # \<tau>) pf \<noteq> None) \<and>
       
   160           (\<forall>f f' im. is_file (a # \<tau>) f \<and> parent f' = Some f \<and> inum_of_file (a # \<tau>) f' = Some im \<longrightarrow> False) \<and>
       
   161           (\<forall>f f' im. f \<in> files_hung_by_del (a # \<tau>) \<and> inum_of_file (a # \<tau>) f' = Some im \<and> parent f' = Some f \<longrightarrow> False)"
       
   162     proof-
       
   163       have vt: "valid \<tau>" using cons by (auto dest:vd_cons)
       
   164       have os: "os_grant \<tau> a" using cons by (auto dest:vt_grant_os)  
       
   165       have fin: "\<forall>f. f \<in> files_hung_by_del \<tau> \<longrightarrow> inum_of_file \<tau> f \<noteq> None" using vt pre by auto
       
   166       have pin: "\<forall>f pf im. parent f = Some pf \<and> inum_of_file \<tau> f = Some im \<longrightarrow> inum_of_file \<tau> pf \<noteq> None" 
       
   167         using vt pre apply (erule_tac impE, simp) by ((erule_tac conjE)+, assumption)
       
   168       have fns: "\<forall>f f' im. is_file \<tau> f \<and> parent f' = Some f \<and> inum_of_file \<tau> f' = Some im \<longrightarrow> False"
       
   169         using vt pre apply (erule_tac impE, simp) by ((erule_tac conjE)+, assumption)
       
   170       have hns: "\<forall>f f' im. f \<in> files_hung_by_del \<tau> \<and> inum_of_file \<tau> f' = Some im \<and> parent f' = Some f \<longrightarrow> False" 
       
   171         using vt pre apply (erule_tac impE, simp) by ((erule_tac conjE)+, assumption)
       
   172       have ain: "\<forall>f' f im. f \<preceq> f' \<and> inum_of_file \<tau> f' = Some im \<longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   173       proof 
       
   174         fix f' 
       
   175         show " \<forall>f im. f \<preceq> f' \<and> inum_of_file \<tau> f' = Some im \<longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   176         proof (induct f')
       
   177           case Nil show ?case by (auto simp: no_junior_def)
       
   178         next
       
   179           case (Cons a f') 
       
   180           assume pre:"\<forall>f im. f \<preceq> f' \<and> inum_of_file \<tau> f' = Some im \<longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   181           show "\<forall>f im. f \<preceq> a # f' \<and> inum_of_file \<tau> (a # f') = Some im \<longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   182           proof clarify
       
   183             fix f im
       
   184             assume h1: "f \<preceq> a # f'"
       
   185               and  h2: "inum_of_file \<tau> (a # f') = Some im"
       
   186             show "\<exists>y. inum_of_file \<tau> f = Some y"
       
   187             proof-
       
   188               have h3: "\<exists> y. inum_of_file \<tau> f' = Some y" 
       
   189               proof-
       
   190                 have "parent (a # f') = Some f'" by simp
       
   191                 hence "\<exists> y. inum_of_file \<tau> f' = Some y" using pin h2 by blast
       
   192                 with h1 show ?thesis by simp
       
   193               qed
       
   194               from h1 have "f = a # f' \<or> f = f' \<or> f \<preceq> f'" by (induct f, auto simp:no_junior_def)
       
   195               moreover have "f = a # f' \<Longrightarrow> \<exists>y. inum_of_file \<tau> f = Some y" using h2 by simp
       
   196               moreover have "f = f' \<Longrightarrow> \<exists>y. inum_of_file \<tau> f = Some y"  using h3 by simp
       
   197               moreover have "f \<preceq> f' \<Longrightarrow> \<exists>y. inum_of_file \<tau> f = Some y" using pre h3 by simp
       
   198               ultimately show ?thesis by auto
       
   199             qed
       
   200           qed
       
   201         qed
       
   202       qed
       
   203 
       
   204       have fin': "\<And> f. f \<in> files_hung_by_del \<tau> \<Longrightarrow> \<exists> im. inum_of_file \<tau> f = Some im" using fin by auto
       
   205       have pin': "\<And> f pf im. \<lbrakk>parent f = Some pf; inum_of_file \<tau> f = Some im\<rbrakk> \<Longrightarrow> \<exists> im'. inum_of_file \<tau> pf = Some im'"
       
   206         using pin by auto
       
   207       have fns': "\<And> f f' im. \<lbrakk>is_file \<tau> f; parent f' = Some f; inum_of_file \<tau> f' = Some im\<rbrakk> \<Longrightarrow> False" using fns by auto
       
   208       have fns'': "\<And> f f' im im'. \<lbrakk>itag_of_inum \<tau> im = Some Tag_FILE; inum_of_file \<tau> f = Some im; parent f' = Some f; inum_of_file \<tau> f' = Some im'\<rbrakk> \<Longrightarrow> False"
       
   209         by (rule_tac f = f and f' = f' in fns', auto simp:is_file_def)
       
   210       have hns': "\<And> f f' im. \<lbrakk>f \<in> files_hung_by_del \<tau>; inum_of_file \<tau> f' = Some im; parent f' = Some f\<rbrakk> \<Longrightarrow> False" using hns by auto
       
   211       have ain': "\<And> f f' im. \<lbrakk>f \<preceq> f'; inum_of_file \<tau> f' = Some im\<rbrakk> \<Longrightarrow> \<exists> im'. inum_of_file \<tau> f = Some im'" using ain by auto
       
   212       have dns': "\<And> f f' im. \<lbrakk>dir_is_empty \<tau> f; parent f' = Some f; inum_of_file \<tau> f' = Some im\<rbrakk> \<Longrightarrow> False"
       
   213         apply (auto simp:dir_is_empty_def current_files_def is_dir_def split:option.splits)
       
   214         by (erule_tac x = f' in allE, simp add:noJ_Anc parent_is_ancen, drule parent_is_parent, simp+)
       
   215 
       
   216       have "\<forall> f. f \<in> files_hung_by_del (a # \<tau>) \<longrightarrow> inum_of_file (a # \<tau>) f \<noteq> None"
       
   217         apply (clarify, case_tac a) using os fin
       
   218         apply (auto simp:files_hung_by_del.simps inum_of_file.simps os_grant.simps current_files_def 
       
   219                    split:if_splits option.splits)
       
   220         done
       
   221       moreover 
       
   222       have "\<forall>f pf im. parent f = Some pf \<and> inum_of_file (a # \<tau>) f = Some im \<longrightarrow> inum_of_file (a # \<tau>) pf \<noteq> None" 
       
   223         apply (clarify, case_tac a)
       
   224         using vt os pin'
       
   225         apply (auto simp:os_grant.simps current_files_def inum_of_file.simps split:if_splits option.splits)
       
   226         apply (drule_tac f = pf and f' = f in hns', simp, simp, simp)
       
   227         apply (drule_tac f = list and f' = f in fns', simp, simp, simp)
       
   228         apply (drule_tac f = list and f' = f in dns', simp, simp, simp)
       
   229         done
       
   230       moreover have "\<forall>f f' im. is_file (a # \<tau>) f \<and> parent f' = Some f \<and> inum_of_file (a # \<tau>) f' = Some im \<longrightarrow> False"
       
   231         apply (clarify, case_tac a)    
       
   232         using vt os fns''
       
   233         apply (auto simp:os_grant.simps current_files_def inum_of_file.simps itag_of_inum.simps 
       
   234                          is_file_def is_dir_def 
       
   235                     dest:ios's_im_in_cim iof's_im_in_cim
       
   236                    split:if_splits option.splits t_inode_tag.splits t_socket_type.splits)
       
   237         apply (drule_tac f = f' and pf = list in pin', simp, simp)
       
   238         apply (drule_tac f = f' and pf = list2 in pin', simp, simp)
       
   239         done
       
   240       moreover have "\<forall>f f' im. f \<in> files_hung_by_del (a # \<tau>) \<and> inum_of_file (a # \<tau>) f' = Some im \<and> 
       
   241                                parent f' = Some f \<longrightarrow> False"
       
   242         apply (clarify, case_tac a)     
       
   243         using vt os hns'
       
   244         apply (auto simp:os_grant.simps current_files_def inum_of_file.simps files_hung_by_del.simps 
       
   245                    split:if_splits option.splits t_sock_addr.splits)
       
   246         apply (drule fns', simp+)
       
   247         done
       
   248       ultimately show ?thesis by blast
       
   249     qed
       
   250   qed
       
   251 qed
       
   252     
       
   253 (**************** hung file in current ***********************)
       
   254 
       
   255 lemma hung_file_has_inum:"\<lbrakk>f \<in> files_hung_by_del \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   256 by (drule file_leveling[rule_format], blast)
       
   257 
       
   258 lemma hung_file_has_inum': "\<lbrakk>f \<in> files_hung_by_del \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> \<exists> im. inum_of_file \<tau> f = Some im"
       
   259 by (auto dest:hung_file_has_inum)
       
   260 
       
   261 lemma hung_file_in_current: "\<lbrakk>f \<in> files_hung_by_del \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> f \<in> current_files \<tau>"
       
   262 by (clarsimp simp add:current_files_def hung_file_has_inum')
       
   263 
       
   264 lemma parentf_has_inum: "\<lbrakk>parent f = Some pf; inum_of_file \<tau> f = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> inum_of_file \<tau> pf \<noteq> None"
       
   265 by (drule file_leveling[rule_format], blast)
       
   266 
       
   267 lemma parentf_has_inum': "\<lbrakk>parent f = Some pf; inum_of_file \<tau> f = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> \<exists> im'. inum_of_file \<tau> pf = Some im'"
       
   268 by (auto dest:parentf_has_inum)
       
   269 
       
   270 lemma parentf_in_current: "\<lbrakk>parent f = Some pf; f \<in> current_files \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> pf \<in> current_files \<tau>"
       
   271 by (clarsimp simp add:current_files_def parentf_has_inum')
       
   272 
       
   273 lemma parentf_in_current': "\<lbrakk>a # pf \<in> current_files \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> pf \<in> current_files \<tau>"
       
   274 apply (subgoal_tac "parent (a # pf) = Some pf")
       
   275 by (erule parentf_in_current, simp+)
       
   276 
       
   277 lemma ancenf_has_inum_aux: "\<forall> f im. f \<preceq> f' \<and> inum_of_file \<tau> f' = Some im \<and> valid \<tau> \<longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   278 proof (induct f')
       
   279   case Nil show ?case by (auto simp: no_junior_def)
       
   280 next
       
   281   case (Cons a f') 
       
   282   assume pre:"\<forall>f im. f \<preceq> f' \<and> inum_of_file \<tau> f' = Some im \<and> valid \<tau> \<longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   283   show "\<forall>f im. f \<preceq> a # f' \<and> inum_of_file \<tau> (a # f') = Some im \<and> valid \<tau> \<longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   284   proof clarify
       
   285     fix f im
       
   286     assume h1: "f \<preceq> a # f'"
       
   287       and  h2: "inum_of_file \<tau> (a # f') = Some im"
       
   288       and  h3: "valid \<tau>"
       
   289     show "\<exists>y. inum_of_file \<tau> f = Some y"
       
   290     proof-
       
   291       have h4: "\<exists> y. inum_of_file \<tau> f' = Some y" 
       
   292       proof-
       
   293         have "parent (a # f') = Some f'" by simp
       
   294         hence "\<exists> y. inum_of_file \<tau> f' = Some y" using parentf_has_inum' h2 h3 by blast
       
   295         with h1 show ?thesis by simp
       
   296       qed
       
   297       from h1 have "f = a # f' \<or> f = f' \<or> f \<preceq> f'" by (induct f, auto simp:no_junior_def)
       
   298       moreover have "f = a # f' \<Longrightarrow> \<exists>y. inum_of_file \<tau> f = Some y" using h2 by simp
       
   299       moreover have "f = f' \<Longrightarrow> \<exists>y. inum_of_file \<tau> f = Some y"  using h4 by simp
       
   300       moreover have "f \<preceq> f' \<Longrightarrow> \<exists>y. inum_of_file \<tau> f = Some y" using pre h3 h4 by simp
       
   301       ultimately show ?thesis by auto
       
   302     qed
       
   303   qed
       
   304 qed
       
   305 
       
   306 lemma ancenf_has_inum: "\<lbrakk>f \<preceq> f'; inum_of_file \<tau> f' = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   307 by (rule ancenf_has_inum_aux[rule_format], auto)
       
   308 
       
   309 lemma ancenf_has_inum': "\<lbrakk>f \<preceq> f'; inum_of_file \<tau> f' = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> \<exists> im'. inum_of_file \<tau> f = Some im'"
       
   310 by (auto dest:ancenf_has_inum)
       
   311 
       
   312 lemma ancenf_in_current: "\<lbrakk>f \<preceq> f'; f' \<in> current_files \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> f \<in> current_files \<tau>"
       
   313 by (simp add:current_files_def, erule exE, simp add:ancenf_has_inum')
       
   314 
       
   315 lemma file_has_no_son: "\<lbrakk>is_file \<tau> f; parent f' = Some f; inum_of_file \<tau> f' = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> False"
       
   316 by (drule file_leveling[rule_format], blast)
       
   317 
       
   318 lemma file_has_no_son': "\<lbrakk>is_file \<tau> f; parent f' = Some f; f' \<in> current_files \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> False"
       
   319 by (simp add:current_files_def, erule exE, auto intro:file_has_no_son)
       
   320 
       
   321 lemma hung_file_no_son: "\<lbrakk>f \<in> files_hung_by_del \<tau>; valid \<tau>; inum_of_file \<tau> f' = Some im; parent f' = Some f\<rbrakk> \<Longrightarrow> False"
       
   322 by (drule file_leveling[rule_format], blast)
       
   323 
       
   324 lemma hung_file_no_son': "\<lbrakk>f \<in> files_hung_by_del \<tau>; valid \<tau>; f' \<in> current_files \<tau>; parent f' = Some f\<rbrakk> \<Longrightarrow> False"
       
   325 by (simp add:current_files_def, erule exE, auto intro:hung_file_no_son)
       
   326 
       
   327 lemma hung_file_no_des_aux: "\<forall> f. f \<in> files_hung_by_del \<tau> \<and> valid \<tau> \<and> f' \<in> current_files \<tau> \<and> f \<preceq> f' \<and> f \<noteq> f' \<longrightarrow> False"
       
   328 proof (induct f')
       
   329   case Nil 
       
   330   show ?case
       
   331     by (auto simp:files_hung_by_del.simps current_files_def inum_of_file.simps no_junior_def split:if_splits option.splits)
       
   332 next
       
   333   case (Cons a pf)
       
   334   assume pre: "\<forall>f. f \<in> files_hung_by_del \<tau> \<and> valid \<tau> \<and> pf \<in> current_files \<tau> \<and> f \<preceq> pf \<and> f \<noteq> pf\<longrightarrow> False"
       
   335   show ?case
       
   336   proof clarify
       
   337     fix f
       
   338     assume h1: "f \<in> files_hung_by_del \<tau>"
       
   339       and  h2: "valid \<tau>"
       
   340       and  h3: "a # pf \<in> current_files \<tau>"
       
   341       and  h4: "f \<preceq> a # pf"
       
   342       and  h5: "f \<noteq> a # pf"
       
   343     have h6: "parent (a # pf) = Some pf" by simp
       
   344     with h2 h3 have h7: "pf \<in> current_files \<tau>" by (drule_tac parentf_in_current, auto)
       
   345     from h4 h5 have h8: "f \<preceq> pf" by (erule_tac no_juniorE, case_tac zs, auto simp:no_junior_def)
       
   346     show False
       
   347     proof (cases "f = pf")
       
   348       case True with h6 h2 h3 h1
       
   349       show False by (auto intro!:hung_file_no_son')
       
   350     next
       
   351       case False with pre h1 h2 h7 h8 
       
   352       show False by blast
       
   353     qed
       
   354   qed
       
   355 qed
       
   356 
       
   357 lemma hung_file_no_des: "\<lbrakk>f \<in> files_hung_by_del \<tau>; valid \<tau>; f' \<in> current_files \<tau>; f \<preceq> f'; f \<noteq> f'\<rbrakk> \<Longrightarrow> False"
       
   358 by (rule hung_file_no_des_aux[rule_format], blast)
       
   359 
       
   360 lemma hung_file_is_leaf: "\<lbrakk>f \<in> files_hung_by_del \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> is_file \<tau> f \<or> dir_is_empty \<tau> f"
       
   361 apply (frule hung_file_has_inum', simp, erule exE)
       
   362 apply (auto simp add:is_file_def dir_is_empty_def is_dir_def  dest:finum_has_itag finum_has_ftag split:option.splits if_splits t_inode_tag.splits)
       
   363 by (simp add: noJ_Anc, auto dest:hung_file_no_des)
       
   364 
       
   365 
       
   366 
       
   367 (************** file_of_proc_fd in current ********************)
       
   368 
       
   369 lemma file_of_pfd_imp_inode_aux: "\<forall> p f. file_of_proc_fd \<tau> p fd = Some f \<and> valid \<tau> \<longrightarrow> inum_of_file \<tau> f \<noteq> None" 
       
   370 apply (induct \<tau>)
       
   371 apply (clarsimp simp add:file_of_proc_fd.simps inum_of_file.simps init_filefd_prop1 init_file_has_inum)
       
   372 apply ((rule_tac allI|rule_tac impI|erule_tac conjE)+, frule vd_cons, frule vt_grant_os, case_tac a)
       
   373 apply (auto simp:inum_of_file.simps file_of_proc_fd.simps os_grant.simps current_files_def 
       
   374            split:if_splits option.splits)
       
   375 apply (simp add:pfdof_simp3)+
       
   376 apply (simp add:proc_fd_of_file_def)+  
       
   377 done
       
   378 
       
   379 lemma file_of_pfd_imp_inode': "\<lbrakk>file_of_proc_fd \<tau> p fd = Some f; valid \<tau>\<rbrakk> \<Longrightarrow> inum_of_file \<tau> f \<noteq> None"
       
   380 by (rule file_of_pfd_imp_inode_aux[rule_format], blast)
       
   381 
       
   382 lemma file_of_pfd_imp_inode: "\<lbrakk>file_of_proc_fd \<tau> p fd = Some f; valid \<tau>\<rbrakk> \<Longrightarrow> \<exists> im. inum_of_file \<tau> f = Some im"
       
   383 by (auto dest!:file_of_pfd_imp_inode')
       
   384 
       
   385 lemma file_of_pfd_in_current: "\<lbrakk>file_of_proc_fd \<tau> p fd = Some f; valid \<tau>\<rbrakk> \<Longrightarrow> f \<in> current_files \<tau>"
       
   386 by (auto dest!:file_of_pfd_imp_inode' simp:current_files_def)
       
   387 
       
   388 
       
   389 (*************** file_of_proc_fd is file *********************)
       
   390 
       
   391 lemma file_of_pfd_is_file_tag:
       
   392   "\<lbrakk>file_of_proc_fd \<tau> p fd = Some f; valid \<tau>; inum_of_file \<tau> f = Some im\<rbrakk> \<Longrightarrow> itag_of_inum \<tau> im = Some Tag_FILE"
       
   393 apply (induct \<tau> arbitrary:p, simp)
       
   394 apply (drule init_filefd_prop5, simp add:is_init_file_def split:option.splits t_inode_tag.splits)
       
   395 apply (frule vd_cons, frule vt_grant_os, simp, case_tac a)
       
   396 by (auto split:option.splits t_inode_tag.splits if_splits t_socket_type.splits 
       
   397           dest:file_of_pfd_imp_inode' iof's_im_in_cim
       
   398           simp:is_file_def is_dir_def dir_is_empty_def current_files_def)
       
   399 
       
   400 lemma file_of_pfd_is_file:
       
   401   "\<lbrakk>file_of_proc_fd \<tau> p fd = Some f; valid \<tau>\<rbrakk> \<Longrightarrow> is_file \<tau> f"
       
   402 apply (frule file_of_pfd_imp_inode, simp, erule exE)
       
   403 apply (drule file_of_pfd_is_file_tag, simp+)
       
   404 by (simp add:is_file_def)
       
   405 
       
   406 lemma file_of_pfd_is_file':
       
   407   "\<lbrakk>file_of_proc_fd \<tau> p fd = Some f; is_dir \<tau> f; valid \<tau>\<rbrakk> \<Longrightarrow> False"
       
   408 by (drule file_of_pfd_is_file, auto simp:is_file_def is_dir_def split:option.splits t_inode_tag.splits)
       
   409 
       
   410 (************** parent file / ancestral file is dir *******************)
       
   411 
       
   412 lemma parentf_is_dir_aux: "\<forall> f pf. parent f = Some pf \<and> inum_of_file \<tau> f = Some im \<and> inum_of_file \<tau> pf = Some ipm \<and> valid \<tau> \<longrightarrow> itag_of_inum \<tau> ipm = Some Tag_DIR"
       
   413 apply (induct \<tau>)
       
   414 apply (clarsimp simp:inum_of_file.simps itag_of_inum.simps init_parent_file_is_dir')
       
   415 apply (clarify, frule vd_cons, frule vt_grant_os, case_tac a)
       
   416 apply (auto simp:inum_of_file.simps itag_of_inum.simps os_grant.simps 
       
   417                  current_files_def is_dir_def is_file_def 
       
   418             dest: ios's_im_in_cim iof's_im_in_cim
       
   419            split:if_splits option.splits t_sock_addr.splits t_inode_tag.splits t_socket_type.splits)
       
   420 apply (drule parentf_has_inum', simp, simp, simp)+
       
   421 done
       
   422 
       
   423 lemma parentf_has_dirtag: 
       
   424   "\<lbrakk>parent f = Some pf; inum_of_file \<tau> f = Some im; inum_of_file \<tau> pf = Some ipm; valid \<tau>\<rbrakk> 
       
   425    \<Longrightarrow> itag_of_inum \<tau> ipm = Some Tag_DIR"
       
   426 by (auto intro:parentf_is_dir_aux[rule_format])
       
   427 
       
   428 lemma parentf_is_dir': "\<lbrakk>parent f = Some pf; inum_of_file \<tau> f = Some im; valid \<tau>\<rbrakk> \<Longrightarrow> is_dir \<tau> pf"
       
   429 apply (frule parentf_has_inum', simp+, erule exE, simp add:is_dir_def split:t_inode_tag.splits option.splits)
       
   430 by (auto dest:parentf_has_dirtag)
       
   431 
       
   432 lemma parentf_is_dir: "\<lbrakk>parent f = Some pf; f \<in> current_files \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> is_dir \<tau> pf"
       
   433 by (clarsimp simp:current_files_def parentf_is_dir')
       
   434 
       
   435 lemma ancenf_is_dir_aux: "\<forall> f. f \<preceq> f' \<and> f \<noteq> f' \<and> f' \<in> current_files \<tau> \<and> valid \<tau> \<longrightarrow> is_dir \<tau> f"
       
   436 proof (induct f')
       
   437   case Nil show ?case
       
   438     by (auto simp:current_files_def no_junior_def)
       
   439 next 
       
   440   case (Cons a pf)
       
   441   assume pre: "\<forall>f. f \<preceq> pf \<and> f \<noteq> pf \<and> pf \<in> current_files \<tau> \<and> valid \<tau> \<longrightarrow> is_dir \<tau> f"
       
   442   show ?case
       
   443   proof clarify
       
   444     fix f
       
   445     assume h1: "f \<preceq> a # pf"
       
   446       and  h2: "f \<noteq> a # pf"
       
   447       and  h3: "a # pf \<in> current_files \<tau>"
       
   448       and  h4: "valid \<tau>"
       
   449     have h5: "parent (a # pf) = Some pf" by simp
       
   450     with h3 h4 have h6: "pf \<in> current_files \<tau>" by (drule_tac parentf_in_current, auto)
       
   451     from h1 h2 have h7: "f \<preceq> pf" by (erule_tac no_juniorE, case_tac zs, auto simp:no_junior_def)
       
   452     show "is_dir \<tau> f"
       
   453     proof (cases "f = pf")
       
   454       case True with h3 h4 h5 show "is_dir \<tau> f" by (drule_tac parentf_is_dir, auto)
       
   455     next
       
   456       case False with pre h6 h7 h4 show "is_dir \<tau> f" by blast
       
   457     qed
       
   458   qed
       
   459 qed
       
   460 
       
   461 lemma ancenf_is_dir: "\<lbrakk>f \<preceq> f'; f \<noteq> f'; f' \<in> current_files \<tau>; valid \<tau>\<rbrakk> \<Longrightarrow> is_dir \<tau> f"
       
   462 by (auto intro:ancenf_is_dir_aux[rule_format])
       
   463 
       
   464 (************* rebuild current_files simpset ***********************)
       
   465 
       
   466 lemma current_files_nil: "current_files [] = init_files"
       
   467 apply (simp add:current_files_def inum_of_file.simps)
       
   468 by (auto dest:inof_has_file_tag init_file_has_inum)
       
   469 
       
   470 lemma current_files_open: "current_files (Open p f flags fd (Some i) # \<tau>) = insert f (current_files \<tau>)"
       
   471 by (auto simp add:current_files_def inum_of_file.simps split:option.splits)
       
   472 
       
   473 lemma current_files_open': "current_files (Open p f flags fd None # \<tau>) = current_files \<tau>"
       
   474 by (simp add:current_files_def inum_of_file.simps split:option.splits)
       
   475 
       
   476 lemma current_files_closefd: "current_files (CloseFd p fd # \<tau>) = (
       
   477      case (file_of_proc_fd \<tau> p fd) of
       
   478        Some f \<Rightarrow> ( if ((proc_fd_of_file \<tau> f = {(p, fd)}) \<and> (f \<in> files_hung_by_del \<tau>))
       
   479                    then current_files \<tau> - {f}
       
   480                    else current_files \<tau>)
       
   481      | _      \<Rightarrow> current_files \<tau>                                  )"
       
   482 by (auto simp:current_files_def inum_of_file.simps split:option.splits)
       
   483 
       
   484 lemma current_files_unlink: "current_files (UnLink p f # \<tau>) = (if (proc_fd_of_file \<tau> f = {}) then (current_files \<tau>) - {f} else current_files \<tau>)"
       
   485 by (auto simp:current_files_def inum_of_file.simps split:option.splits)
       
   486 
       
   487 lemma current_files_rmdir: "current_files (Rmdir p f # \<tau>) = (if (proc_fd_of_file \<tau> f = {}) then current_files \<tau> - {f} else current_files \<tau>)"
       
   488 by (auto simp:current_files_def inum_of_file.simps split:option.splits)
       
   489 
       
   490 lemma current_files_mkdir: "current_files (Mkdir p f ino # \<tau>) = insert f (current_files \<tau>)"
       
   491 by (auto simp:current_files_def inum_of_file.simps split:option.splits)
       
   492 
       
   493 lemma current_files_linkhard: 
       
   494   "valid (LinkHard p f\<^isub>1 f\<^isub>2 # \<tau>) \<Longrightarrow> current_files (LinkHard p f\<^isub>1 f\<^isub>2 # \<tau>) = insert f\<^isub>2 (current_files \<tau>)"
       
   495 apply (frule vt_grant_os, frule vd_cons)
       
   496 by (auto simp:current_files_def inum_of_file.simps os_grant.simps split:option.splits)
       
   497 
       
   498 (*
       
   499 lemma rename_renaming_decom:
       
   500   "\<lbrakk>f\<^isub>3 \<preceq> file_after_rename f\<^isub>2 f\<^isub>3 f; Rename p f\<^isub>2 f\<^isub>3 # valid \<tau>; f \<in> current_files \<tau>\<rbrakk> \<Longrightarrow> f\<^isub>2 \<preceq> f"
       
   501 apply (case_tac "f\<^isub>2 \<preceq> f", simp)
       
   502 apply (simp add:file_after_rename_def split:if_splits)
       
   503 by (frule vd_cons, frule vt_grant_os, auto simp:os_grant.simps dest!:ancenf_in_current)
       
   504 
       
   505 lemma rename_renaming_decom':
       
   506   "\<lbrakk>\<not> f\<^isub>3 \<preceq> file_after_rename f\<^isub>2 f\<^isub>3 f; Rename p f\<^isub>2 f\<^isub>3 # valid \<tau>; f \<in> current_files \<tau>\<rbrakk> \<Longrightarrow> \<not> f\<^isub>2 \<preceq> f"
       
   507 by (case_tac "f\<^isub>2 \<preceq> f", drule_tac f\<^isub>3 = f\<^isub>3 in file_renaming_prop1, simp+)
       
   508 
       
   509 lemma current_files_rename: "Rename p f\<^isub>2 f\<^isub>3 # valid \<tau> \<Longrightarrow> current_files (Rename p f\<^isub>2 f\<^isub>3 # \<tau>) = {file_after_rename f\<^isub>2 f\<^isub>3 f\<^isub>1| f\<^isub>1. f\<^isub>1 \<in> current_files \<tau>}"
       
   510 apply (frule vt_grant_os, frule vd_cons)
       
   511 apply (auto simp:current_files_def inum_of_file.simps os_grant.simps split:if_splits option.splits)
       
   512 apply (rule_tac x = x in exI, simp add:file_after_rename_def)
       
   513 apply (frule_tac f\<^isub>2 = f\<^isub>2 in file_renaming_prop1', drule_tac f\<^isub>2 = f\<^isub>2 in file_renaming_prop5')
       
   514 apply (erule_tac x = "file_before_rename f\<^isub>2 f\<^isub>3 x" in allE, simp)
       
   515 apply (rule_tac x = x in exI, simp add:file_after_rename_def)
       
   516 apply (drule_tac a = f\<^isub>3 and b = f\<^isub>2 in no_junior_conf, simp, simp)
       
   517 apply (drule_tac f = f\<^isub>3 and f' = f\<^isub>2 in ancenf_has_inum', simp, simp, simp)
       
   518 apply (drule_tac f\<^isub>2 = f\<^isub>2 in rename_renaming_decom, simp, simp add:current_files_def, simp add:file_renaming_prop5)
       
   519 apply (drule_tac f\<^isub>2 = f\<^isub>2 in rename_renaming_decom', simp, simp add:current_files_def)
       
   520 apply (simp add:file_after_rename_def)
       
   521 apply (drule_tac f\<^isub>2 = f\<^isub>2 in rename_renaming_decom', simp, simp add:current_files_def)
       
   522 apply (simp add:file_after_rename_def)
       
   523 done
       
   524 *)
       
   525 
       
   526 lemma current_files_other:
       
   527   "\<lbrakk>\<forall> p f flag fd opt. e \<noteq> Open p f flag fd opt;
       
   528     \<forall> p fd. e \<noteq> CloseFd p fd;
       
   529     \<forall> p f. e \<noteq> UnLink p f;
       
   530     \<forall> p f. e \<noteq> Rmdir p f;
       
   531     \<forall> p f i. e \<noteq> Mkdir p f i;
       
   532     \<forall> p f f'. e \<noteq> LinkHard p f f'\<rbrakk> \<Longrightarrow> current_files (e # \<tau>) = current_files \<tau>"
       
   533 by (case_tac e, auto simp:current_files_def inum_of_file.simps)
       
   534 
       
   535 lemmas current_files_simps = current_files_nil current_files_open current_files_open' 
       
   536                              current_files_closefd current_files_unlink current_files_rmdir 
       
   537                              current_files_mkdir current_files_linkhard current_files_other
       
   538 
       
   539 
       
   540 (******************** is_file simpset *********************)
       
   541 
       
   542 lemma is_file_nil: "is_file [] = is_init_file"
       
   543 by (auto simp:is_init_file_def is_file_def init_inum_of_file_props intro!:ext split:option.splits)
       
   544 
       
   545 lemma is_file_open:
       
   546   "valid (Open p f flags fd opt # s) \<Longrightarrow> 
       
   547    is_file (Open p f flags fd opt # s) = (if (opt = None) then is_file s else (is_file s) (f:= True))"
       
   548 apply (frule vd_cons, drule vt_grant_os, rule ext)
       
   549 apply (auto dest:finum_has_itag iof's_im_in_cim 
       
   550            split:if_splits option.splits t_inode_tag.splits 
       
   551             simp:is_file_def current_files_def)
       
   552 done
       
   553 
       
   554 lemma is_file_closefd:
       
   555   "valid (CloseFd p fd # s) \<Longrightarrow> is_file (CloseFd p fd # s) = (
       
   556      case (file_of_proc_fd s p fd) of
       
   557        Some f \<Rightarrow> ( if ((proc_fd_of_file s f = {(p, fd)}) \<and> (f \<in> files_hung_by_del s))
       
   558                    then (is_file s) (f := False) 
       
   559                    else is_file s)
       
   560      | _      \<Rightarrow> is_file s                                   )"
       
   561 apply (frule vd_cons, drule vt_grant_os, rule ext)
       
   562 apply (auto dest:finum_has_itag iof's_im_in_cim 
       
   563            split:if_splits option.splits t_inode_tag.splits 
       
   564             simp:is_file_def)
       
   565 done
       
   566 
       
   567 lemma is_file_unlink:
       
   568   "valid (UnLink p f # s) \<Longrightarrow> is_file (UnLink p f # s) = (
       
   569      if (proc_fd_of_file s f = {}) then (is_file s) (f := False) else is_file s)"
       
   570 apply (frule vd_cons, drule vt_grant_os, rule ext)
       
   571 apply (auto dest:finum_has_itag iof's_im_in_cim 
       
   572            split:if_splits option.splits t_inode_tag.splits 
       
   573             simp:is_file_def)
       
   574 done
       
   575 
       
   576 lemma is_file_linkhard:
       
   577   "valid (LinkHard p f f' # s) \<Longrightarrow> is_file (LinkHard p f f' # s) = (is_file s) (f' := True)"
       
   578 apply (frule vd_cons, drule vt_grant_os, rule ext)
       
   579 apply (auto dest:finum_has_itag iof's_im_in_cim 
       
   580            split:if_splits option.splits t_inode_tag.splits 
       
   581             simp:is_file_def)
       
   582 done
       
   583 
       
   584 lemma is_file_other:
       
   585   "\<lbrakk>valid (e # \<tau>); 
       
   586     \<forall> p f flag fd opt. e \<noteq> Open p f flag fd opt;
       
   587     \<forall> p fd. e \<noteq> CloseFd p fd;
       
   588     \<forall> p f. e \<noteq> UnLink p f;
       
   589     \<forall> p f f'. e \<noteq> LinkHard p f f'\<rbrakk> \<Longrightarrow> is_file (e # \<tau>) = is_file \<tau>"
       
   590 apply (frule vd_cons, drule vt_grant_os, rule_tac ext, case_tac e)
       
   591 apply (auto dest:finum_has_itag iof's_im_in_cim intro!:ext
       
   592            split:if_splits option.splits t_inode_tag.split t_socket_type.splits
       
   593             simp:is_file_def dir_is_empty_def is_dir_def current_files_def)
       
   594 done
       
   595 
       
   596 lemma file_dir_conflict: "\<lbrakk>is_file s f; is_dir s f\<rbrakk> \<Longrightarrow> False"
       
   597 by (auto simp:is_file_def is_dir_def split:option.splits t_inode_tag.splits)
       
   598 
       
   599 lemma is_file_not_dir: "is_file s f \<Longrightarrow> \<not> is_dir s f"
       
   600 by (rule notI, erule file_dir_conflict, simp)
       
   601 
       
   602 lemma is_dir_not_file: "is_dir s f \<Longrightarrow> \<not> is_file s f"
       
   603 by (rule notI, erule file_dir_conflict, simp)
       
   604 
       
   605 lemmas is_file_simps = is_file_nil is_file_open is_file_closefd is_file_unlink is_file_linkhard is_file_other
       
   606 
       
   607 (********* is_dir simpset **********)
       
   608 
       
   609 lemma is_dir_nil: "is_dir [] = is_init_dir"
       
   610 by (auto simp:is_init_dir_def is_dir_def init_inum_of_file_props intro!:ext split:option.splits)
       
   611 
       
   612 lemma is_dir_mkdir: "valid (Mkdir p f i # s) \<Longrightarrow> is_dir (Mkdir p f i # s) = (is_dir s) (f := True)"
       
   613 apply (frule vd_cons, drule vt_grant_os, rule_tac ext)
       
   614 apply (auto dest:finum_has_itag iof's_im_in_cim intro!:ext
       
   615            split:if_splits option.splits t_inode_tag.split t_socket_type.splits
       
   616             simp:is_dir_def dir_is_empty_def is_dir_def current_files_def)
       
   617 done
       
   618 
       
   619 lemma is_dir_rmdir: "valid (Rmdir p f # s) \<Longrightarrow> is_dir (Rmdir p f # s) = (is_dir s) (f := False)"
       
   620 apply (frule vd_cons, drule vt_grant_os, rule_tac ext)
       
   621 apply (auto dest:finum_has_itag iof's_im_in_cim intro!:ext
       
   622            split:if_splits option.splits t_inode_tag.split t_socket_type.splits
       
   623             simp:is_dir_def dir_is_empty_def is_dir_def current_files_def)
       
   624 apply (drule pfdof_simp2)
       
   625 apply (drule file_of_pfd_is_file, simp)
       
   626 apply (simp add:is_file_def split:t_inode_tag.splits option.splits)
       
   627 done
       
   628 
       
   629 lemma is_dir_other:
       
   630   "\<lbrakk>valid (e # s);
       
   631     \<forall> p f. e \<noteq> Rmdir p f;
       
   632     \<forall> p f i. e \<noteq> Mkdir p f i\<rbrakk> \<Longrightarrow> is_dir (e # s) = is_dir s"
       
   633 apply (frule vd_cons, drule vt_grant_os, rule_tac ext, case_tac e)
       
   634 apply (auto dest:finum_has_itag iof's_im_in_cim intro!:ext
       
   635            split:if_splits option.splits t_inode_tag.split t_socket_type.splits
       
   636             simp:is_file_def dir_is_empty_def is_dir_def current_files_def)
       
   637 apply (drule file_of_pfd_is_file, simp)
       
   638 apply (simp add:is_file_def split:t_inode_tag.splits option.splits)
       
   639 done
       
   640 
       
   641 lemmas is_dir_simps = is_dir_nil is_dir_mkdir is_dir_rmdir is_dir_other
       
   642 
       
   643 (*********** no root dir involved ***********)
       
   644 
       
   645 lemma root_is_dir: "valid s \<Longrightarrow> is_dir s []"
       
   646 apply (induct s, simp add:is_dir_nil root_is_init_dir)
       
   647 apply (frule vd_cons, frule vt_grant_os, case_tac a)
       
   648 apply (auto simp:is_dir_simps)
       
   649 done
       
   650 
       
   651 lemma root_is_dir': "\<lbrakk>is_file s []; valid s\<rbrakk> \<Longrightarrow> False"
       
   652 apply (drule root_is_dir)
       
   653 apply (erule file_dir_conflict, simp)
       
   654 done
       
   655 
       
   656 lemma noroot_execve:
       
   657   "valid (Execve p f fds # s) \<Longrightarrow> f \<noteq> []"
       
   658 by (frule vd_cons, drule vt_grant_os, auto dest!:root_is_dir')
       
   659 
       
   660 lemma noroot_execve':
       
   661   "valid (Execve p [] fds # s) \<Longrightarrow> False"
       
   662 by (drule noroot_execve, simp)
       
   663 
       
   664 lemma noroot_open:
       
   665   "valid (Open p f flags fd opt # s) \<Longrightarrow> f \<noteq> []"
       
   666 by (frule vd_cons, drule vt_grant_os, auto dest!:root_is_dir' split:option.splits)
       
   667 
       
   668 lemma noroot_open':
       
   669   "valid (Open p [] flags fd opt # s) \<Longrightarrow> False"
       
   670 by (drule noroot_open, simp)
       
   671 
       
   672 lemma noroot_filefd':
       
   673   "\<lbrakk>file_of_proc_fd s p fd = Some []; valid s\<rbrakk> \<Longrightarrow> False"
       
   674 apply (induct s arbitrary:p, simp) 
       
   675 apply (drule init_filefd_prop5, erule root_is_init_dir')
       
   676 apply (frule vd_cons, frule vt_grant_os, case_tac a)
       
   677 apply (auto split:if_splits option.splits dest!:root_is_dir')
       
   678 done
       
   679 
       
   680 lemma noroot_filefd:
       
   681   "\<lbrakk>file_of_proc_fd s p fd = Some f; valid s\<rbrakk> \<Longrightarrow> f \<noteq> []"
       
   682 by (rule notI, simp, erule noroot_filefd', simp)
       
   683 
       
   684 lemma noroot_unlink:
       
   685   "valid (UnLink p f # s) \<Longrightarrow> f \<noteq> []"
       
   686 by (frule vd_cons, drule vt_grant_os, auto dest!:root_is_dir')
       
   687 
       
   688 lemma noroot_unlink':
       
   689   "valid (UnLink p [] # s) \<Longrightarrow> False"
       
   690 by (drule noroot_unlink, simp)
       
   691 
       
   692 lemma noroot_rmdir:
       
   693   "valid (Rmdir p f # s) \<Longrightarrow> f \<noteq> []"
       
   694 by (frule vd_cons, drule vt_grant_os, auto dest!:root_is_dir')
       
   695 
       
   696 lemma noroot_rmdir':
       
   697   "valid (Rmdir p [] # s) \<Longrightarrow> False"
       
   698 by (drule noroot_rmdir, simp)
       
   699 
       
   700 lemma noroot_mkdir:
       
   701   "valid (Mkdir p f inum # s) \<Longrightarrow> f \<noteq> []"
       
   702 by (frule vd_cons, drule vt_grant_os, auto dest!:root_is_dir')
       
   703 
       
   704 lemma noroot_mkdir':
       
   705   "valid (Mkdir p [] inum # s) \<Longrightarrow> False"
       
   706 by (drule noroot_mkdir, simp)
       
   707 
       
   708 lemma noroot_linkhard:
       
   709   "valid (LinkHard p f f' # s) \<Longrightarrow> f \<noteq> [] \<and> f' \<noteq> []"
       
   710 by (frule vd_cons, drule vt_grant_os, auto dest!:root_is_dir')
       
   711 
       
   712 lemma noroot_linkhard':
       
   713   "valid (LinkHard p [] f # s) \<Longrightarrow> False"
       
   714 by (drule noroot_linkhard, simp)
       
   715 
       
   716 lemma noroot_linkhard'':
       
   717   "valid (LinkHard p f [] # s) \<Longrightarrow> False"
       
   718 by (drule noroot_linkhard, simp)
       
   719 
       
   720 lemma noroot_truncate:
       
   721   "valid (Truncate p f len # s) \<Longrightarrow> f \<noteq> []"
       
   722 by (frule vd_cons, drule vt_grant_os, auto dest!:root_is_dir')
       
   723 
       
   724 lemma noroot_truncate':
       
   725   "valid (Truncate p [] len # s) \<Longrightarrow> False"
       
   726 by (drule noroot_truncate, simp)
       
   727 
       
   728 lemmas noroot_events = noroot_execve noroot_open noroot_filefd noroot_unlink noroot_rmdir
       
   729   noroot_mkdir noroot_linkhard noroot_truncate
       
   730 
       
   731 lemmas noroot_events' = noroot_execve' noroot_open' noroot_filefd' noroot_unlink' noroot_rmdir'
       
   732   noroot_mkdir' noroot_linkhard' noroot_linkhard'' noroot_truncate'
       
   733 
       
   734 end
       
   735 
       
   736 end