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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 | // SPDX-License-Identifier: GPL-2.0-only /* * Manage printing of source lines * Copyright (c) 2017, Intel Corporation. * Author: Andi Kleen */ #include <linux/list.h> #include <linux/zalloc.h> #include <stdlib.h> #include <sys/mman.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> #include <assert.h> #include <string.h> #include "srccode.h" #include "debug.h" #include "util.h" #define MAXSRCCACHE (32*1024*1024) #define MAXSRCFILES 64 #define SRC_HTAB_SZ 64 struct srcfile { struct hlist_node hash_nd; struct list_head nd; char *fn; char **lines; char *map; unsigned numlines; size_t maplen; }; static struct hlist_head srcfile_htab[SRC_HTAB_SZ]; static LIST_HEAD(srcfile_list); static long map_total_sz; static int num_srcfiles; static unsigned shash(unsigned char *s) { unsigned h = 0; while (*s) h = 65599 * h + *s++; return h ^ (h >> 16); } static int countlines(char *map, int maplen) { int numl; char *end = map + maplen; char *p = map; if (maplen == 0) return 0; numl = 0; while (p < end && (p = memchr(p, '\n', end - p)) != NULL) { numl++; p++; } if (p < end) numl++; return numl; } static void fill_lines(char **lines, int maxline, char *map, int maplen) { int l; char *end = map + maplen; char *p = map; if (maplen == 0 || maxline == 0) return; l = 0; lines[l++] = map; while (p < end && (p = memchr(p, '\n', end - p)) != NULL) { if (l >= maxline) return; lines[l++] = ++p; } if (p < end) lines[l] = p; } static void free_srcfile(struct srcfile *sf) { list_del_init(&sf->nd); hlist_del(&sf->hash_nd); map_total_sz -= sf->maplen; munmap(sf->map, sf->maplen); zfree(&sf->lines); zfree(&sf->fn); free(sf); num_srcfiles--; } static struct srcfile *find_srcfile(char *fn) { struct stat st; struct srcfile *h; int fd; unsigned long sz; unsigned hval = shash((unsigned char *)fn) % SRC_HTAB_SZ; hlist_for_each_entry (h, &srcfile_htab[hval], hash_nd) { if (!strcmp(fn, h->fn)) { /* Move to front */ list_del(&h->nd); list_add(&h->nd, &srcfile_list); return h; } } /* Only prune if there is more than one entry */ while ((num_srcfiles > MAXSRCFILES || map_total_sz > MAXSRCCACHE) && srcfile_list.next != &srcfile_list) { assert(!list_empty(&srcfile_list)); h = list_entry(srcfile_list.prev, struct srcfile, nd); free_srcfile(h); } fd = open(fn, O_RDONLY); if (fd < 0 || fstat(fd, &st) < 0) { pr_debug("cannot open source file %s\n", fn); return NULL; } h = malloc(sizeof(struct srcfile)); if (!h) return NULL; h->fn = strdup(fn); if (!h->fn) goto out_h; h->maplen = st.st_size; sz = (h->maplen + page_size - 1) & ~(page_size - 1); h->map = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0); close(fd); if (h->map == (char *)-1) { pr_debug("cannot mmap source file %s\n", fn); goto out_fn; } h->numlines = countlines(h->map, h->maplen); h->lines = calloc(h->numlines, sizeof(char *)); if (!h->lines) goto out_map; fill_lines(h->lines, h->numlines, h->map, h->maplen); list_add(&h->nd, &srcfile_list); hlist_add_head(&h->hash_nd, &srcfile_htab[hval]); map_total_sz += h->maplen; num_srcfiles++; return h; out_map: munmap(h->map, sz); out_fn: zfree(&h->fn); out_h: free(h); return NULL; } /* Result is not 0 terminated */ char *find_sourceline(char *fn, unsigned line, int *lenp) { char *l, *p; struct srcfile *sf = find_srcfile(fn); if (!sf) return NULL; line--; if (line >= sf->numlines) return NULL; l = sf->lines[line]; if (!l) return NULL; p = memchr(l, '\n', sf->map + sf->maplen - l); *lenp = p - l; return l; } |