491B 200203

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GEF/EEE 491B 2002/03 symtbl.ppt
Produits de développement et maintenance du
logiciel Software Work Products and Maintenance
C.D. (Terry) Shepard, BSc, MA, PhD, PEng SB 4019
x6031 Home 541 0631 email shepard_at_rmc.ca
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symtbl - Module Interface Specification (MIS) - 1
Interface syntax define ST_MAXSYMS 50
/maximum number of symbols/ define
ST_MAXSYMLEN 20 /maximum symbol length/
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symtbl MIS - 2
Interface semantics state variables tbl set of
tuple of (sym string, loc integer) state
invariant 1. tbl ST_MAXSYMS 2. (t 0
tbl)(t.sym ST_MAXSYMLEN) 3. (t1 , t2 0
tbl)(t1 t2 v t1.sym t2.sym)
assumptions st_s_init is called before any of
the other access routine. All string parameters
are legal C strings.
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symtbl MIS - 3
access routine semantics 1 st_s_init transition
tbl exceptions none st_s_add(sym, loc)
transition tbl tbl c ltsym, locgt
exceptions exc (sym gt ST_MAXSYMLEN
st_maxlen (loc1)(ltsym, loc1gt 0
tbl) st_exsym tbl ST_MAXSYMS
st_full) st_g_exsym(sym) output out
(loc)(ltsym, locgt 0 tbl) exceptions none
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symtbl MIS - 4
access routine semantics 2 st_s_loc(sym,
loc) transition tbl (tbl - ltsym, loc1gt) c
ltsym, locgt
where ltsym, loc1gt 0 tbl exceptions exc
(loc1)(ltsym, loc1gt 0 tbl) st_notexsym st_g_lo
c(sym) output out loc, where ltsym, locgt 0
tbl exceptions exc (loc1)(ltsym, loc1gt 0
tbl) st_notexsym st_g_siz output out
tbl exceptions none
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symtbl MID - 1
state variables struct char symST_MAXSYMLEN1
int loc tblST_MAXSYMS int tblcnt state
invariant 1. Every symbol in tbl0..tblcnt-1
contains a null. 2. There are no duplicate
symbols in tbl0..tblcnt-1. 3. tblcnt 0
0..ST_MAXSYMS
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symtbl MID - 2
abstraction function tbl ltsym, locgt(i0
0..tblcnt-1)(sym tbli.sym v loc
tbli.loc) access routine semantics
1 st_s_init transition tblcnt
0 exceptions none st_s_add(sym, loc)
transition tblcnt, tbltblcnt tblcnt 1,
ltsym, locgt exceptions exc (sym gt
ST_MAXSYMLEN st_maxlen findsym(sym)
NOTFOUND st_exsym tblCNT ST_MAXSYMS
st_full)
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symtbl MID - 3
access routine semantics 2 st_g_exsym(sym)
output out findsym(sym) NOTFOUND
exceptions none st_s_loc(sym, loc)
transition tblfindsym(sym).loc loc
exceptions exc findsym(sym) NOTFOUND
st_notexsym st_g_loc(sym) output out
tblfindsym(sym).loc exceptions exc
findsym(sym) NOTFOUND st_notexsym st_g_siz
output out tblcnt exceptions none
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symtbl MID - 4
local constants define NOTFOUND -1 local
functions findsym string v integer findsym(s)
(i0 0..tblcnt-1)(s tbli.sym i true
NOTFOUND)
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symtbl makefile 1
INC ../include CFLAGS -I(INC) export
symtbl.o symtbl_e.o symtbl_b symtbl_b.o
symtbl.o cc -o symtbl_b symtbl_b.o
symtbl.o tcov symtbl_b.o cc -a -c -I(INC)
symtbl.c cc -a -o symtbl_b symtbl_b.o
symtbl.o symtbl_b tcov symtbl.c rm -f symtbl.o
tcov version is dangerous to leave around
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symtbl makefile 2
symtbl_i symtbl_i.o symtbl_e.o symtbl.o cc -o
symtbl_i symtbl_i.o symtbl_e.o symtbl.o symtbl_b.
o (INC)/symtbl.h (INC)/system.h symtbl_i.o
(INC)/symtbl.h (INC)/system.h symtbl.o
(INC)/symtbl.h (INC)/system.h symtbl_e.o
(INC)/symtbl.h (INC)/system.h symtbl_b.c
symtbl.script pgmgen symtbl.script mv test.c
symtbl_b.c lint symtbl_b.c lint -I(INC)
symtbl_b.c symtbl.c clean rm -f symtbl_i
symtbl_b .o symtbl_b.c symtbl.c.tcov symtbl.c.d
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symtbl.h
/constants/ define ST_MAXSYMS 50
/maximum number of symbols/ define
ST_MAXSYMLEN 20 /maximum symbol
length/ /types/ /access
routines/ void st_s_init() void
st_s_add(char sym,int loc) int
st_g_siz() /boolean/ int st_g_exsym(char
sym) void st_s_loc(char sym,int loc) int
st_g_loc(char sym) void st_g_dump() /for
testing purposes only/ /exception
handlers/ void st_exsym() void
st_maxlen() void st_notexsym() void st_full()
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symtbl.c 1

• include "system.h"
• include "symtbl.h"
• /constants/
• define NOTFOUND -1
• /types/
• /module state/
• static struct
• char symST_MAXSYMLEN1 /symbol value/
• int loc /symbol location/
• tblST_MAXSYMS /one entry per symbol/
• static int tblcnt /number of symbols in tbl/
• /local functions/

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symtbl.c 2

• /access routines/
• void st_s_init()
• tblcnt 0
• void st_s_add(char sym,int loc)
• if (strlen(sym) gt ST_MAXSYMLEN)
• st_maxlen()
• return
• else if (findsym(sym) ! NOTFOUND)
• st_exsym()
• return
• else if (tblcnt ST_MAXSYMS)
• st_full()
• return

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symtbl.c 3

• void st_s_loc(char sym,int loc)
• int i
• i findsym(sym)
• if (i NOTFOUND)
• st_notexsym()
• return
• tbli.loc loc
• int st_g_loc(char sym)
• int i
• i findsym(sym)
• if (i NOTFOUND)
• st_notexsym()

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symtbl_e.c

• include "system.h"
• include "symtbl.h"
• void st_exsym()
• fprintf(sy_excfilp,"Exception st_exsym
  occurred\n")
• void st_maxlen()
• fprintf(sy_excfilp,"Exception st_maxlen
  occurred\n")
• void st_notexsym()
• fprintf(sy_excfilp,"Exception st_notexsym
  occurred\n")
• void st_full()

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symtbl.tplan 1

• Assumptions
• ST_MAXSYMLEN gt length of ST_MAXSYMS - 1 in
  string form
• ST_MAXINTLEN gt 0
•  
• Test environment
• PGMGEN driver
• no stubs
•  
• Test-case selection strategy
•  
• special values
•  
• module state
• number of symbols in table 0, 1, ST_MAXSYMS/2,
  ST_MAXSYMS
• symbol length short, ST_MAXSYMLEN
•  
• access routine parameters
• st_s_add strings of length 0, 1, ST_MAXSYMLEN
  1, 2 ST_MAXSYMLEN
• st_s_add, st_s_loc, st_g_loc, st_g_exsym empty
  string

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symtbl.tplan 2

• test cases (cond)
•  
• normal
•  
• check st_g_exsym for empty string in empty table
• add the empty string, check and change its
  location
• for each special module state
• check table length
• check that a very long symbol is not in table
• for each i in 0..ST_MAXSYMS-1
• if i in 0..t_siz - 1
• check t_sym(i) in table with correct location
• check st_s_loc resets location
• else
• check t_sym(i) not in table
•  
•  
• Test implementation strategy
•  

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symtbl.scr 1

• module
• st_
•  
• accprogs
• lts_init,s_add,g_exsym,s_loc,g_loc,g_sizgt
•  
• exceptions
• ltexsym,maxlen,notexsym,fullgt
•  
• globcod
• include "system.h"
• include "symtbl.h"
•  
• define T_FILLCHAR ''
•  
• static int i,cur
•  
• static struct

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symtbl.scr 2

• static void t_init()
• cur -1
• static char t_mksym(i,len)
• int i,len
• static char buf2ST_MAXSYMLEN1
• int j
•  
• sprintf(buf,"d",i) /convert i to ASCII/
• if (len gt strlen(buf))
• for (j strlen(buf) j lt len j) /pad right
  with ''/
• bufj T_FILLCHAR
• buflen '\0' /add string terminator/
• return(buf)

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symtbl.scr 3

• static int t_siz()
• return(tblcur.syms)
• static char t_sym(i)
• int i
• return(t_mksym(i,tblcur.symlen))
•  
• static int t_loc(i)
• int i
• return(10i)
•  
• cases

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symtbl.scr 4

• /exceptions (cond)/
• /set and get locations for symbols not in the
  table/
• lts_loc(t_mksym(t_siz(),0),0), notexsym, dc, dc,
  dcgt
• lts_loc("",0), notexsym, dc, dc, dcgt
• ltg_loc(t_mksym(t_siz(),0)), notexsym, dc, dc,
  dcgt
• ltg_loc(""), notexsym, dc, dc, dcgt
•  
• /add every symbol in the table/
• for (i 0 i lt t_siz() i)
• lts_add(t_sym(i),0), exsym, dc, dc, dcgt
• t_next()
• /normal case/

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symtbl.scr 5

• /normal case (cond)/
• t_init()
• t_next()
• while (!t_end())
• /check table length/
• lt , noexc, g_siz(), t_siz(), intgt
• /check that a very long symbol is not in
  table/
• lt , noexc, g_exsym(t_mksym(0,2ST_MAXSYMLEN)),
  0, boolgt
• for (i 0 i lt ST_MAXSYMS i)
• if (i lt t_siz())
• /check t_sym(i) in table with correct
  location/
• lt , noexc, g_exsym(t_sym(i)), 1, boolgt
• lt , noexc, g_loc(t_sym(i)), t_loc(i), intgt
• /check s_loc resets location/

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symtbl_i.c 1

• include "system.h"
• include "symtbl.h"
• define QUIT 0
• define S_INIT 1
• define S_ADD 2
• define G_EXSYM 3
• define S_LOC 4
• define G_LOC 5
• define G_SIZ 6
• define G_DUMP 7
• define BUFLEN 80
• FILE sy_excfilp stderr

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symtbl_i.c 2

• int nextcall()
• int reply
• char s81
• do
• printf("\nEnter command\n")
• printf("\t0quit\n")
• printf("\t1s_init\n")
• printf("\t2s_add\n")
• printf("\t3g_exsym\n")
• printf("\t4s_loc\n")
• printf("\t5g_loc\n")
• printf("\t6g_siz\n")
• printf("\t7g_dump")
• gets(s)
• if (sscanf(s,"d",reply) ! 1)
• reply -1 /user error - stay in loop/
• while (reply lt 0 reply gt G_DUMP)

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symtbl_i.c 3

• main()
• int reply,i
• char s80
• while ((replynextcall()) ! QUIT)
• switch(reply)
• case S_INIT
• st_s_init()
• break
• case S_ADD
• printf("Enter sym")
• gets(s)
• sscanf(s,"s",s)
• i readint("Enter loc")
• st_s_add(s,i)
• break
• case G_EXSYM
• printf("Enter sym")

case G_LOC printf("Enter sym") gets(s)
sscanf(s,"s",s) i st_g_loc(s) print
f("returns d\n",i) break case G_SIZ i
st_g_siz() printf("returns
d\n",i) break case G_DUMP st_g_dump()
break return(0)