summaryrefslogtreecommitdiffabout
Unidiff
Diffstat (more/less context) (ignore whitespace changes)
-rw-r--r--cache.c33
1 files changed, 24 insertions, 9 deletions
diff --git a/cache.c b/cache.c
index add647e..6847202 100644
--- a/cache.c
+++ b/cache.c
@@ -53,38 +53,42 @@ static int open_slot(struct cache_slot *slot)
53 53
54 slot->bufsize = read(slot->cache_fd, slot->buf, sizeof(slot->buf)); 54 slot->bufsize = read(slot->cache_fd, slot->buf, sizeof(slot->buf));
55 if (slot->bufsize < 0) 55 if (slot->bufsize < 0)
56 return errno; 56 return errno;
57 57
58 bufz = memchr(slot->buf, 0, slot->bufsize); 58 bufz = memchr(slot->buf, 0, slot->bufsize);
59 if (bufz) 59 if (bufz)
60 bufkeylen = bufz - slot->buf; 60 bufkeylen = bufz - slot->buf;
61 61
62 slot->match = bufkeylen == slot->keylen && 62 slot->match = bufkeylen == slot->keylen &&
63 !memcmp(slot->key, slot->buf, bufkeylen + 1); 63 !memcmp(slot->key, slot->buf, bufkeylen + 1);
64 64
65 return 0; 65 return 0;
66} 66}
67 67
68/* Close the active cache slot */ 68/* Close the active cache slot */
69static void close_slot(struct cache_slot *slot) 69static int close_slot(struct cache_slot *slot)
70{ 70{
71 int err = 0;
71 if (slot->cache_fd > 0) { 72 if (slot->cache_fd > 0) {
72 close(slot->cache_fd); 73 if (close(slot->cache_fd))
73 slot->cache_fd = -1; 74 err = errno;
75 else
76 slot->cache_fd = -1;
74 } 77 }
78 return err;
75} 79}
76 80
77/* Print the content of the active cache slot (but skip the key). */ 81/* Print the content of the active cache slot (but skip the key). */
78static int print_slot(struct cache_slot *slot) 82static int print_slot(struct cache_slot *slot)
79{ 83{
80 ssize_t i, j = 0; 84 ssize_t i, j = 0;
81 85
82 i = lseek(slot->cache_fd, slot->keylen + 1, SEEK_SET); 86 i = lseek(slot->cache_fd, slot->keylen + 1, SEEK_SET);
83 if (i != slot->keylen + 1) 87 if (i != slot->keylen + 1)
84 return errno; 88 return errno;
85 89
86 while((i=read(slot->cache_fd, slot->buf, sizeof(slot->buf))) > 0) 90 while((i=read(slot->cache_fd, slot->buf, sizeof(slot->buf))) > 0)
87 j = write(STDOUT_FILENO, slot->buf, i); 91 j = write(STDOUT_FILENO, slot->buf, i);
88 92
89 if (j < 0) 93 if (j < 0)
90 return errno; 94 return errno;
@@ -103,94 +107,105 @@ static int is_expired(struct cache_slot *slot)
103 107
104/* Check if the slot has been modified since we opened it. 108/* Check if the slot has been modified since we opened it.
105 * NB: If stat() fails, we pretend the file is modified. 109 * NB: If stat() fails, we pretend the file is modified.
106 */ 110 */
107static int is_modified(struct cache_slot *slot) 111static int is_modified(struct cache_slot *slot)
108{ 112{
109 struct stat st; 113 struct stat st;
110 114
111 if (stat(slot->cache_name, &st)) 115 if (stat(slot->cache_name, &st))
112 return 1; 116 return 1;
113 return (st.st_ino != slot->cache_st.st_ino || 117 return (st.st_ino != slot->cache_st.st_ino ||
114 st.st_mtime != slot->cache_st.st_mtime || 118 st.st_mtime != slot->cache_st.st_mtime ||
115 st.st_size != slot->cache_st.st_size); 119 st.st_size != slot->cache_st.st_size);
116} 120}
117 121
118/* Close an open lockfile */ 122/* Close an open lockfile */
119static void close_lock(struct cache_slot *slot) 123static int close_lock(struct cache_slot *slot)
120{ 124{
125 int err = 0;
121 if (slot->lock_fd > 0) { 126 if (slot->lock_fd > 0) {
122 close(slot->lock_fd); 127 if (close(slot->lock_fd))
123 slot->lock_fd = -1; 128 err = errno;
129 else
130 slot->lock_fd = -1;
124 } 131 }
132 return err;
125} 133}
126 134
127/* Create a lockfile used to store the generated content for a cache 135/* Create a lockfile used to store the generated content for a cache
128 * slot, and write the slot key + \0 into it. 136 * slot, and write the slot key + \0 into it.
129 * Returns 0 on success and errno otherwise. 137 * Returns 0 on success and errno otherwise.
130 */ 138 */
131static int lock_slot(struct cache_slot *slot) 139static int lock_slot(struct cache_slot *slot)
132{ 140{
133 slot->lock_fd = open(slot->lock_name, O_RDWR|O_CREAT|O_EXCL, 141 slot->lock_fd = open(slot->lock_name, O_RDWR|O_CREAT|O_EXCL,
134 S_IRUSR|S_IWUSR); 142 S_IRUSR|S_IWUSR);
135 if (slot->lock_fd == -1) 143 if (slot->lock_fd == -1)
136 return errno; 144 return errno;
137 write(slot->lock_fd, slot->key, slot->keylen + 1); 145 if (write(slot->lock_fd, slot->key, slot->keylen + 1) < 0)
146 return errno;
138 return 0; 147 return 0;
139} 148}
140 149
141/* Release the current lockfile. If `replace_old_slot` is set the 150/* Release the current lockfile. If `replace_old_slot` is set the
142 * lockfile replaces the old cache slot, otherwise the lockfile is 151 * lockfile replaces the old cache slot, otherwise the lockfile is
143 * just deleted. 152 * just deleted.
144 */ 153 */
145static int unlock_slot(struct cache_slot *slot, int replace_old_slot) 154static int unlock_slot(struct cache_slot *slot, int replace_old_slot)
146{ 155{
147 int err; 156 int err;
148 157
149 if (replace_old_slot) 158 if (replace_old_slot)
150 err = rename(slot->lock_name, slot->cache_name); 159 err = rename(slot->lock_name, slot->cache_name);
151 else 160 else
152 err = unlink(slot->lock_name); 161 err = unlink(slot->lock_name);
153 return err; 162
163 if (err)
164 return errno;
165
166 return 0;
154} 167}
155 168
156/* Generate the content for the current cache slot by redirecting 169/* Generate the content for the current cache slot by redirecting
157 * stdout to the lock-fd and invoking the callback function 170 * stdout to the lock-fd and invoking the callback function
158 */ 171 */
159static int fill_slot(struct cache_slot *slot) 172static int fill_slot(struct cache_slot *slot)
160{ 173{
161 int tmp; 174 int tmp;
162 175
163 /* Preserve stdout */ 176 /* Preserve stdout */
164 tmp = dup(STDOUT_FILENO); 177 tmp = dup(STDOUT_FILENO);
165 if (tmp == -1) 178 if (tmp == -1)
166 return errno; 179 return errno;
167 180
168 /* Redirect stdout to lockfile */ 181 /* Redirect stdout to lockfile */
169 if (dup2(slot->lock_fd, STDOUT_FILENO) == -1) 182 if (dup2(slot->lock_fd, STDOUT_FILENO) == -1)
170 return errno; 183 return errno;
171 184
172 /* Generate cache content */ 185 /* Generate cache content */
173 slot->fn(slot->cbdata); 186 slot->fn(slot->cbdata);
174 187
175 /* Restore stdout */ 188 /* Restore stdout */
176 if (dup2(tmp, STDOUT_FILENO) == -1) 189 if (dup2(tmp, STDOUT_FILENO) == -1)
177 return errno; 190 return errno;
178 191
179 /* Close the temporary filedescriptor */ 192 /* Close the temporary filedescriptor */
180 close(tmp); 193 if (close(tmp))
194 return errno;
195
181 return 0; 196 return 0;
182} 197}
183 198
184/* Crude implementation of 32-bit FNV-1 hash algorithm, 199/* Crude implementation of 32-bit FNV-1 hash algorithm,
185 * see http://www.isthe.com/chongo/tech/comp/fnv/ for details 200 * see http://www.isthe.com/chongo/tech/comp/fnv/ for details
186 * about the magic numbers. 201 * about the magic numbers.
187 */ 202 */
188#define FNV_OFFSET 0x811c9dc5 203#define FNV_OFFSET 0x811c9dc5
189#define FNV_PRIME 0x01000193 204#define FNV_PRIME 0x01000193
190 205
191unsigned long hash_str(const char *str) 206unsigned long hash_str(const char *str)
192{ 207{
193 unsigned long h = FNV_OFFSET; 208 unsigned long h = FNV_OFFSET;
194 unsigned char *s = (unsigned char *)str; 209 unsigned char *s = (unsigned char *)str;
195 210
196 if (!s) 211 if (!s)