1 |
#ifndef lint |
2 |
static const char RCSid[] = "$Id: sort.c,v 1.6 2003/07/14 20:02:29 schorsch Exp $"; |
3 |
#endif |
4 |
/* |
5 |
* Sorting routines for meta-files |
6 |
*/ |
7 |
|
8 |
#include "platform.h" /* [_]snprintf() */ |
9 |
#include "rtprocess.h" /* getpid() */ |
10 |
#include "rterror.h" |
11 |
#include "meta.h" |
12 |
|
13 |
|
14 |
#define PBSIZE 1000 /* max size of sort block */ |
15 |
/* maxalloc must be >= this */ |
16 |
|
17 |
#define NFILES 4 /* number of sort files */ |
18 |
|
19 |
|
20 |
static void treemerge(int height, int nt, int nf, PLIST *pl, |
21 |
int (*pcmp)(), FILE *ofp); |
22 |
static void sendsort( PLIST *pl, int (*pcmp)()); |
23 |
static void order(PRIMITIVE *pa[], int n, PLIST *pl); |
24 |
static char * tfname( int lvl, int num); |
25 |
|
26 |
/* |
27 |
* This sort routine does a combination quicksort and |
28 |
* n-ary mergesort |
29 |
*/ |
30 |
|
31 |
|
32 |
void |
33 |
sort( /* sort primitives according to pcmp */ |
34 |
FILE *infp, |
35 |
int (*pcmp)() /* compares pointers to pointers to primitives! */ |
36 |
) |
37 |
{ |
38 |
PRIMITIVE *prims[PBSIZE]; /* pointers to primitives */ |
39 |
PLIST primlist; /* our primitives list */ |
40 |
int nprims; |
41 |
short done; |
42 |
|
43 |
do { |
44 |
|
45 |
for (nprims = 0; nprims < PBSIZE; nprims++) { /* read to global */ |
46 |
|
47 |
if ((prims[nprims] = palloc()) == NULL) |
48 |
error(SYSTEM, "memory exhausted in sort"); |
49 |
|
50 |
readp(prims[nprims], infp); |
51 |
|
52 |
if (isglob(prims[nprims]->com)) |
53 |
break; |
54 |
} |
55 |
|
56 |
qsort(prims, nprims, sizeof(*prims), pcmp); /* sort pointer array */ |
57 |
|
58 |
if (nprims < PBSIZE) /* tack on global if one */ |
59 |
nprims++; |
60 |
|
61 |
order(prims, nprims, &primlist); /* make array into list */ |
62 |
|
63 |
sendsort(&primlist, pcmp); /* send to merge sorter */ |
64 |
|
65 |
done = primlist.pbot->com == PEOF; |
66 |
|
67 |
plfree(&primlist); /* free up array */ |
68 |
|
69 |
} while (!done); |
70 |
|
71 |
} |
72 |
|
73 |
|
74 |
|
75 |
|
76 |
|
77 |
/* |
78 |
* The following routine merges up to NFILES sorted primitive files |
79 |
* with 0 or 1 primitive lists. Each set of primitives can end with |
80 |
* 0 or 1 global commands. |
81 |
*/ |
82 |
|
83 |
void |
84 |
pmergesort( /* merge sorted files with list */ |
85 |
|
86 |
FILE *fi[], /* array of input files */ |
87 |
int nf, /* number of input files */ |
88 |
PLIST *pl, /* sorted list */ |
89 |
int (*pcmp)(), /* comparison function, takes primitive handles */ |
90 |
FILE *ofp /* output file */ |
91 |
) |
92 |
{ |
93 |
PRIMITIVE *plp; /* position in list */ |
94 |
PRIMITIVE *pp[NFILES]; /* input primitives */ |
95 |
int minf; |
96 |
PRIMITIVE *minp; |
97 |
register int i; |
98 |
|
99 |
if (pl == NULL) |
100 |
plp = NULL; /* initialize list */ |
101 |
else |
102 |
plp = pl->ptop; |
103 |
|
104 |
for (i = 0; i < nf; i++) { /* initialize input files */ |
105 |
if ((pp[i] = palloc()) == NULL) |
106 |
error(SYSTEM, "memory exhausted in pmergesort"); |
107 |
readp(pp[i], fi[i]); |
108 |
} |
109 |
|
110 |
for ( ; ; ) { |
111 |
|
112 |
if (plp != NULL && isprim(plp->com)) |
113 |
minp = plp; |
114 |
else |
115 |
minp = NULL; |
116 |
|
117 |
for (i = 0; i < nf; i++) |
118 |
if (isprim(pp[i]->com) && |
119 |
(minp == NULL || (*pcmp)(&pp[i], &minp) < 0)) |
120 |
minp = pp[minf=i]; |
121 |
|
122 |
if (minp == NULL) |
123 |
break; |
124 |
|
125 |
writep(minp, ofp); |
126 |
|
127 |
if (minp == plp) |
128 |
plp = plp->pnext; |
129 |
else { |
130 |
fargs(pp[minf]); |
131 |
readp(pp[minf], fi[minf]); |
132 |
} |
133 |
} |
134 |
|
135 |
if (plp != NULL && plp->com != PEOF) |
136 |
writep(plp, ofp); |
137 |
|
138 |
for (i = 0; i < nf; i++) { |
139 |
if (pp[i]->com != PEOF) |
140 |
writep(pp[i], ofp); |
141 |
pfree(pp[i]); |
142 |
} |
143 |
|
144 |
} |
145 |
|
146 |
|
147 |
|
148 |
static void |
149 |
treemerge( /* merge into one file */ |
150 |
|
151 |
int height, int nt, int nf, |
152 |
PLIST *pl, |
153 |
int (*pcmp)(), |
154 |
FILE *ofp |
155 |
) |
156 |
{ |
157 |
FILE *fi[NFILES], *fp; |
158 |
int i; |
159 |
|
160 |
if (nf <= NFILES) { |
161 |
|
162 |
for (i = 0; i < nf; i++) |
163 |
fi[i] = efopen(tfname(height, i + nt*NFILES), "r"); |
164 |
|
165 |
if ((fp = ofp) == NULL) |
166 |
fp = efopen(tfname(height + 1, nt), "w"); |
167 |
|
168 |
pmergesort(fi, nf, pl, pcmp, fp); |
169 |
|
170 |
for (i = 0; i < nf; i++) { |
171 |
fclose(fi[i]); |
172 |
unlink(tfname(height, i + nt*NFILES)); |
173 |
} |
174 |
if (ofp == NULL) { |
175 |
writeof(fp); |
176 |
fclose(fp); |
177 |
} |
178 |
|
179 |
} else { |
180 |
|
181 |
for (i = 0; i < (nf-1)/NFILES; i++) |
182 |
treemerge(height, i, NFILES, NULL, pcmp, NULL); |
183 |
|
184 |
treemerge(height, (nf-1)/NFILES, (nf-1)%NFILES + 1, pl, pcmp, NULL); |
185 |
|
186 |
treemerge(height + 1, 0, (nf-1)/NFILES + 1, NULL, pcmp, ofp); |
187 |
|
188 |
} |
189 |
|
190 |
} |
191 |
|
192 |
|
193 |
|
194 |
|
195 |
static void |
196 |
sendsort( /* send a sorted list */ |
197 |
|
198 |
PLIST *pl, |
199 |
int (*pcmp)() |
200 |
) |
201 |
{ |
202 |
static int nf = 0, |
203 |
intree = FALSE; |
204 |
FILE *fp; |
205 |
|
206 |
if (isglob(pl->pbot->com)) { |
207 |
|
208 |
/* send sorted output to stdout */ |
209 |
if (intree && nf <= NFILES) |
210 |
|
211 |
treemerge(0, 0, nf, pl, pcmp, stdout); |
212 |
|
213 |
else if (nf%NFILES == 0) |
214 |
|
215 |
if (intree) { |
216 |
treemerge(0, nf/NFILES - 1, NFILES, pl, pcmp, NULL); |
217 |
treemerge(1, 0, nf/NFILES, NULL, pcmp, stdout); |
218 |
} else |
219 |
treemerge(1, 0, nf/NFILES, pl, pcmp, stdout); |
220 |
|
221 |
else { |
222 |
|
223 |
treemerge(0, nf/NFILES, nf%NFILES, pl, pcmp, NULL); |
224 |
treemerge(1, 0, nf/NFILES + 1, NULL, pcmp, stdout); |
225 |
|
226 |
} |
227 |
|
228 |
nf = 0; /* all done */ |
229 |
intree = FALSE; /* reset for next time */ |
230 |
|
231 |
} else if (intree && nf%NFILES == 0) { |
232 |
|
233 |
/* merge NFILES with list */ |
234 |
treemerge(0, nf/NFILES - 1, NFILES, pl, pcmp, NULL); |
235 |
intree = FALSE; |
236 |
|
237 |
} else { |
238 |
|
239 |
/* output straight to temp file */ |
240 |
treemerge(-1, nf++, 0, pl, pcmp, NULL); |
241 |
intree = TRUE; |
242 |
|
243 |
} |
244 |
|
245 |
|
246 |
|
247 |
} |
248 |
|
249 |
|
250 |
|
251 |
static void |
252 |
order( /* order the first n array primitives into list */ |
253 |
|
254 |
PRIMITIVE *pa[], |
255 |
int n, |
256 |
PLIST *pl |
257 |
) |
258 |
{ |
259 |
register int i; |
260 |
|
261 |
for (i = 1; i < n; i++) |
262 |
pa[i-1]->pnext = pa[i]; |
263 |
|
264 |
pa[n-1]->pnext = NULL; |
265 |
pl->ptop = pa[0]; |
266 |
pl->pbot = pa[n-1]; |
267 |
|
268 |
} |
269 |
|
270 |
|
271 |
|
272 |
|
273 |
static char * |
274 |
tfname( /* create temporary file name */ |
275 |
|
276 |
int lvl, int num |
277 |
) |
278 |
{ |
279 |
static char pathbuf[PATH_MAX]; |
280 |
static char fnbuf[PATH_MAX]; |
281 |
static size_t psiz; |
282 |
|
283 |
if (pathbuf[0] == '\0') { /* first time */ |
284 |
temp_directory(pathbuf, sizeof(pathbuf)); |
285 |
psiz = strlen(pathbuf); |
286 |
} |
287 |
snprintf(fnbuf, sizeof(pathbuf)-psiz, |
288 |
"%s/S%d%c%d", pathbuf, getpid(), lvl+'A', num); |
289 |
/*sprintf(fnbuf, "%sS%d%c%d", TDIR, getpid(), lvl+'A', num);*/ |
290 |
|
291 |
return(fnbuf); |
292 |
} |