| 1 | #ifndef _BABELTRACE_FORMAT_CTF_MEMSTREAM_H |
| 2 | #define _BABELTRACE_FORMAT_CTF_MEMSTREAM_H |
| 3 | |
| 4 | /* |
| 5 | * format/ctf/memstream.h |
| 6 | * |
| 7 | * Copyright 2012 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 8 | * |
| 9 | * memstream compatibility layer. |
| 10 | * |
| 11 | * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED |
| 12 | * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. |
| 13 | * |
| 14 | * Permission is hereby granted to use or copy this program |
| 15 | * for any purpose, provided the above notices are retained on all copies. |
| 16 | * Permission to modify the code and to distribute modified code is granted, |
| 17 | * provided the above notices are retained, and a notice that the code was |
| 18 | * modified is included with the above copyright notice. |
| 19 | */ |
| 20 | |
| 21 | #define _GNU_SOURCE |
| 22 | #include <config.h> |
| 23 | |
| 24 | #ifdef BABELTRACE_HAVE_FMEMOPEN |
| 25 | #include <stdio.h> |
| 26 | |
| 27 | static inline |
| 28 | FILE *babeltrace_fmemopen(void *buf, size_t size, const char *mode) |
| 29 | { |
| 30 | return fmemopen(buf, size, mode); |
| 31 | } |
| 32 | |
| 33 | #else /* BABELTRACE_HAVE_FMEMOPEN */ |
| 34 | |
| 35 | #include <stdlib.h> |
| 36 | #include <stdio.h> |
| 37 | |
| 38 | /* |
| 39 | * Fallback for systems which don't have fmemopen. Copy buffer to a |
| 40 | * temporary file, and use that file as FILE * input. |
| 41 | */ |
| 42 | static inline |
| 43 | FILE *babeltrace_fmemopen(void *buf, size_t size, const char *mode) |
| 44 | { |
| 45 | char tmpname[PATH_MAX]; |
| 46 | size_t len; |
| 47 | FILE *fp; |
| 48 | int ret; |
| 49 | |
| 50 | /* |
| 51 | * Support reading only. |
| 52 | */ |
| 53 | if (strcmp(mode, "rb") != 0) { |
| 54 | return NULL; |
| 55 | } |
| 56 | strncpy(tmpname, "/tmp/babeltrace-tmp-XXXXXX", PATH_MAX); |
| 57 | ret = mkstemp(tmpname); |
| 58 | if (ret < 0) { |
| 59 | return NULL; |
| 60 | } |
| 61 | /* |
| 62 | * We need to write to the file. |
| 63 | */ |
| 64 | fp = fdopen(ret, "w+"); |
| 65 | if (!fp) { |
| 66 | goto error_unlink; |
| 67 | } |
| 68 | /* Copy the entire buffer to the file */ |
| 69 | len = fwrite(buf, sizeof(char), size, fp); |
| 70 | if (len != size) { |
| 71 | goto error_close; |
| 72 | } |
| 73 | ret = fseek(fp, 0L, SEEK_SET); |
| 74 | if (ret < 0) { |
| 75 | perror("fseek"); |
| 76 | goto error_close; |
| 77 | } |
| 78 | /* We keep the handle open, but can unlink the file on the VFS. */ |
| 79 | ret = unlink(tmpname); |
| 80 | if (ret < 0) { |
| 81 | perror("unlink"); |
| 82 | } |
| 83 | return fp; |
| 84 | |
| 85 | error_close: |
| 86 | ret = fclose(fp); |
| 87 | if (ret < 0) { |
| 88 | perror("close"); |
| 89 | } |
| 90 | error_unlink: |
| 91 | ret = unlink(tmpname); |
| 92 | if (ret < 0) { |
| 93 | perror("unlink"); |
| 94 | } |
| 95 | return NULL; |
| 96 | } |
| 97 | |
| 98 | #endif /* BABELTRACE_HAVE_FMEMOPEN */ |
| 99 | |
| 100 | #ifdef BABELTRACE_HAVE_OPEN_MEMSTREAM |
| 101 | |
| 102 | #include <stdio.h> |
| 103 | |
| 104 | static inline |
| 105 | FILE *babeltrace_open_memstream(char **ptr, size_t *sizeloc) |
| 106 | { |
| 107 | return open_memstream(ptr, sizeloc); |
| 108 | } |
| 109 | |
| 110 | static inline |
| 111 | int babeltrace_close_memstream(char **buf, size_t *size, FILE *fp) |
| 112 | { |
| 113 | return fclose(fp); |
| 114 | } |
| 115 | |
| 116 | #else /* BABELTRACE_HAVE_OPEN_MEMSTREAM */ |
| 117 | |
| 118 | #include <stdlib.h> |
| 119 | #include <stdio.h> |
| 120 | |
| 121 | /* |
| 122 | * Fallback for systems which don't have open_memstream. Create FILE * |
| 123 | * with babeltrace_open_memstream, but require call to |
| 124 | * babeltrace_close_memstream to flush all data written to the FILE * |
| 125 | * into the buffer (which we allocate). |
| 126 | */ |
| 127 | static inline |
| 128 | FILE *babeltrace_open_memstream(char **ptr, size_t *sizeloc) |
| 129 | { |
| 130 | char tmpname[PATH_MAX]; |
| 131 | int ret; |
| 132 | FILE *fp; |
| 133 | |
| 134 | strncpy(tmpname, "/tmp/babeltrace-tmp-XXXXXX", PATH_MAX); |
| 135 | ret = mkstemp(tmpname); |
| 136 | if (ret < 0) { |
| 137 | return NULL; |
| 138 | } |
| 139 | fp = fdopen(ret, "w+"); |
| 140 | if (!fp) { |
| 141 | goto error_unlink; |
| 142 | } |
| 143 | /* |
| 144 | * babeltrace_flush_memstream will update the buffer content |
| 145 | * with read from fp. No need to keep the file around, just the |
| 146 | * handle. |
| 147 | */ |
| 148 | ret = unlink(tmpname); |
| 149 | if (ret < 0) { |
| 150 | perror("unlink"); |
| 151 | } |
| 152 | return fp; |
| 153 | |
| 154 | error_unlink: |
| 155 | ret = unlink(tmpname); |
| 156 | if (ret < 0) { |
| 157 | perror("unlink"); |
| 158 | } |
| 159 | return NULL; |
| 160 | } |
| 161 | |
| 162 | /* Get file size, allocate buffer, copy. */ |
| 163 | static inline |
| 164 | int babeltrace_close_memstream(char **buf, size_t *size, FILE *fp) |
| 165 | { |
| 166 | size_t len, n; |
| 167 | long pos; |
| 168 | int ret; |
| 169 | |
| 170 | ret = fflush(fp); |
| 171 | if (ret < 0) { |
| 172 | perror("fflush"); |
| 173 | return ret; |
| 174 | } |
| 175 | ret = fseek(fp, 0L, SEEK_END); |
| 176 | if (ret < 0) { |
| 177 | perror("fseek"); |
| 178 | return ret; |
| 179 | } |
| 180 | pos = ftell(fp); |
| 181 | if (ret < 0) { |
| 182 | perror("ftell"); |
| 183 | return ret; |
| 184 | } |
| 185 | *size = pos; |
| 186 | /* add final \0 */ |
| 187 | *buf = calloc(pos + 1, sizeof(char)); |
| 188 | if (!*buf) { |
| 189 | return -ENOMEM; |
| 190 | } |
| 191 | ret = fseek(fp, 0L, SEEK_SET); |
| 192 | if (ret < 0) { |
| 193 | perror("fseek"); |
| 194 | goto error_free; |
| 195 | } |
| 196 | /* Copy the entire file into the buffer */ |
| 197 | n = 0; |
| 198 | clearerr(fp); |
| 199 | while (!feof(fp) && !ferror(fp) && (*size - n > 0)) { |
| 200 | len = fread(*buf, sizeof(char), *size - n, fp); |
| 201 | n += len; |
| 202 | } |
| 203 | if (n != *size) { |
| 204 | ret = -1; |
| 205 | goto error_close; |
| 206 | } |
| 207 | ret = fclose(fp); |
| 208 | if (ret < 0) { |
| 209 | perror("fclose"); |
| 210 | return ret; |
| 211 | } |
| 212 | return 0; |
| 213 | |
| 214 | error_close: |
| 215 | ret = fclose(fp); |
| 216 | if (ret < 0) { |
| 217 | perror("fclose"); |
| 218 | } |
| 219 | error_free: |
| 220 | free(*buf); |
| 221 | *buf = NULL; |
| 222 | return ret; |
| 223 | } |
| 224 | |
| 225 | #endif /* BABELTRACE_HAVE_OPEN_MEMSTREAM */ |
| 226 | |
| 227 | #endif /* _BABELTRACE_FORMAT_CTF_MEMSTREAM_H */ |