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author | Federico Ceratto <federico.ceratto@gmail.com> | 2016-03-30 21:40:42 +0000 |
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committer | Federico Ceratto <federico.ceratto@gmail.com> | 2016-03-30 21:40:42 +0000 |
commit | 9ce153ce7167c11adba8ac225edc7a707e97c6eb (patch) | |
tree | 9f6e849cce2dcc7e5b4e9e6252c843dc2d0787a2 /src/procfile.c | |
download | netdata-9ce153ce7167c11adba8ac225edc7a707e97c6eb.tar.xz netdata-9ce153ce7167c11adba8ac225edc7a707e97c6eb.zip |
Imported Upstream version 1.0.0upstream/1.0.0
Diffstat (limited to 'src/procfile.c')
-rwxr-xr-x | src/procfile.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/src/procfile.c b/src/procfile.c new file mode 100755 index 00000000..7a485795 --- /dev/null +++ b/src/procfile.c @@ -0,0 +1,400 @@ +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <errno.h> +#include <fcntl.h> +#include <string.h> +#include <malloc.h> +#include <ctype.h> +#include <time.h> +#include <sys/time.h> +#include <sys/wait.h> + +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/mman.h> + +#include "common.h" +#include "log.h" +#include "procfile.h" + +#define PF_PREFIX "PROCFILE" + +#define PFWORDS_INCREASE_STEP 200 +#define PFLINES_INCREASE_STEP 10 +#define PROCFILE_INCREMENT_BUFFER 512 + +int procfile_adaptive_initial_allocation = 0; + +// if adaptive allocation is set, these store the +// max values we have seen so far +uint32_t procfile_max_lines = PFLINES_INCREASE_STEP; +uint32_t procfile_max_words = PFWORDS_INCREASE_STEP; +size_t procfile_max_allocation = PROCFILE_INCREMENT_BUFFER; + +// ---------------------------------------------------------------------------- +// An array of words + + +pfwords *pfwords_add(pfwords *fw, char *str) { + // debug(D_PROCFILE, PF_PREFIX ": adding word No %d: '%s'", fw->len, str); + + if(unlikely(fw->len == fw->size)) { + // debug(D_PROCFILE, PF_PREFIX ": expanding words"); + + pfwords *new = realloc(fw, sizeof(pfwords) + (fw->size + PFWORDS_INCREASE_STEP) * sizeof(char *)); + if(unlikely(!new)) { + error(PF_PREFIX ": failed to expand words"); + free(fw); + return NULL; + } + fw = new; + fw->size += PFWORDS_INCREASE_STEP; + } + + fw->words[fw->len++] = str; + + return fw; +} + +pfwords *pfwords_new(void) { + // debug(D_PROCFILE, PF_PREFIX ": initializing words"); + + uint32_t size = (procfile_adaptive_initial_allocation) ? procfile_max_words : PFWORDS_INCREASE_STEP; + + pfwords *new = malloc(sizeof(pfwords) + size * sizeof(char *)); + if(unlikely(!new)) return NULL; + + new->len = 0; + new->size = size; + return new; +} + +void pfwords_reset(pfwords *fw) { + // debug(D_PROCFILE, PF_PREFIX ": reseting words"); + fw->len = 0; +} + +void pfwords_free(pfwords *fw) { + // debug(D_PROCFILE, PF_PREFIX ": freeing words"); + + free(fw); +} + + +// ---------------------------------------------------------------------------- +// An array of lines + +pflines *pflines_add(pflines *fl, uint32_t first_word) { + // debug(D_PROCFILE, PF_PREFIX ": adding line %d at word %d", fl->len, first_word); + + if(unlikely(fl->len == fl->size)) { + // debug(D_PROCFILE, PF_PREFIX ": expanding lines"); + + pflines *new = realloc(fl, sizeof(pflines) + (fl->size + PFLINES_INCREASE_STEP) * sizeof(ffline)); + if(unlikely(!new)) { + error(PF_PREFIX ": failed to expand lines"); + free(fl); + return NULL; + } + fl = new; + fl->size += PFLINES_INCREASE_STEP; + } + + fl->lines[fl->len].words = 0; + fl->lines[fl->len++].first = first_word; + + return fl; +} + +pflines *pflines_new(void) { + // debug(D_PROCFILE, PF_PREFIX ": initializing lines"); + + uint32_t size = (unlikely(procfile_adaptive_initial_allocation)) ? procfile_max_words : PFLINES_INCREASE_STEP; + + pflines *new = malloc(sizeof(pflines) + size * sizeof(ffline)); + if(unlikely(!new)) return NULL; + + new->len = 0; + new->size = size; + return new; +} + +void pflines_reset(pflines *fl) { + // debug(D_PROCFILE, PF_PREFIX ": reseting lines"); + + fl->len = 0; +} + +void pflines_free(pflines *fl) { + // debug(D_PROCFILE, PF_PREFIX ": freeing lines"); + + free(fl); +} + + +// ---------------------------------------------------------------------------- +// The procfile + +#define PF_CHAR_IS_SEPARATOR ' ' +#define PF_CHAR_IS_NEWLINE 'N' +#define PF_CHAR_IS_WORD 'W' + +void procfile_close(procfile *ff) { + debug(D_PROCFILE, PF_PREFIX ": Closing file '%s'", ff->filename); + + if(likely(ff->lines)) pflines_free(ff->lines); + if(likely(ff->words)) pfwords_free(ff->words); + + if(likely(ff->fd != -1)) close(ff->fd); + free(ff); +} + +procfile *procfile_parser(procfile *ff) { + debug(D_PROCFILE, PF_PREFIX ": Parsing file '%s'", ff->filename); + + char *s = ff->data, *e = ff->data, *t = ff->data; + uint32_t l = 0, w = 0; + e += ff->len; + + ff->lines = pflines_add(ff->lines, w); + if(unlikely(!ff->lines)) goto cleanup; + + while(likely(s < e)) { + switch(ff->separators[(int)(*s)]) { + case PF_CHAR_IS_SEPARATOR: + if(likely(s == t)) { + // skip all leading white spaces + t = ++s; + continue; + } + + // end of word + *s = '\0'; + + ff->words = pfwords_add(ff->words, t); + if(unlikely(!ff->words)) goto cleanup; + + ff->lines->lines[l].words++; + w++; + + t = ++s; + continue; + + case PF_CHAR_IS_NEWLINE: + // end of line + *s = '\0'; + + ff->words = pfwords_add(ff->words, t); + if(unlikely(!ff->words)) goto cleanup; + + ff->lines->lines[l].words++; + w++; + + // debug(D_PROCFILE, PF_PREFIX ": ended line %d with %d words", l, ff->lines->lines[l].words); + + ff->lines = pflines_add(ff->lines, w); + if(unlikely(!ff->lines)) goto cleanup; + l++; + + t = ++s; + continue; + + default: + s++; + continue; + } + } + + if(likely(s != t)) { + // the last word + if(likely(ff->len < ff->size)) *s = '\0'; + else { + // we are going to loose the last byte + ff->data[ff->size - 1] = '\0'; + } + + ff->words = pfwords_add(ff->words, t); + if(unlikely(!ff->words)) goto cleanup; + + ff->lines->lines[l].words++; + w++; + } + + return ff; + +cleanup: + error(PF_PREFIX ": Failed to parse file '%s'", ff->filename); + procfile_close(ff); + return NULL; +} + +procfile *procfile_readall(procfile *ff) { + debug(D_PROCFILE, PF_PREFIX ": Reading file '%s'.", ff->filename); + + ssize_t s, r = 1, x; + ff->len = 0; + + while(likely(r > 0)) { + s = ff->len; + x = ff->size - s; + + if(!x) { + debug(D_PROCFILE, PF_PREFIX ": Expanding data buffer for file '%s'.", ff->filename); + + procfile *new = realloc(ff, sizeof(procfile) + ff->size + PROCFILE_INCREMENT_BUFFER); + if(unlikely(!new)) { + error(PF_PREFIX ": Cannot allocate memory for file '%s'", ff->filename); + procfile_close(ff); + return NULL; + } + ff = new; + ff->size += PROCFILE_INCREMENT_BUFFER; + } + + debug(D_PROCFILE, "Reading file '%s', from position %ld with length %ld", ff->filename, s, ff->size - s); + r = read(ff->fd, &ff->data[s], ff->size - s); + if(unlikely(r == -1)) { + if(unlikely(!(ff->flags & PROCFILE_FLAG_NO_ERROR_ON_FILE_IO))) error(PF_PREFIX ": Cannot read from file '%s'", ff->filename); + procfile_close(ff); + return NULL; + } + + ff->len += r; + } + + debug(D_PROCFILE, "Rewinding file '%s'", ff->filename); + if(unlikely(lseek(ff->fd, 0, SEEK_SET) == -1)) { + if(unlikely(!(ff->flags & PROCFILE_FLAG_NO_ERROR_ON_FILE_IO))) error(PF_PREFIX ": Cannot rewind on file '%s'.", ff->filename); + procfile_close(ff); + return NULL; + } + + pflines_reset(ff->lines); + pfwords_reset(ff->words); + + ff = procfile_parser(ff); + + if(unlikely(procfile_adaptive_initial_allocation)) { + if(unlikely(ff->len > procfile_max_allocation)) procfile_max_allocation = ff->len; + if(unlikely(ff->lines->len > procfile_max_lines)) procfile_max_lines = ff->lines->len; + if(unlikely(ff->words->len > procfile_max_words)) procfile_max_words = ff->words->len; + } + + debug(D_PROCFILE, "File '%s' updated.", ff->filename); + return ff; +} + +static void procfile_set_separators(procfile *ff, const char *separators) { + static char def[256] = { [0 ... 255] = 0 }; + int i; + + if(unlikely(!def[255])) { + // this is thread safe + // we check that the last byte is non-zero + // if it is zero, multiple threads may be executing this at the same time + // setting in def[] the exact same values + for(i = 0; likely(i < 256) ;i++) { + if(unlikely(i == '\n' || i == '\r')) def[i] = PF_CHAR_IS_NEWLINE; + else if(unlikely(isspace(i) || !isprint(i))) def[i] = PF_CHAR_IS_SEPARATOR; + else def[i] = PF_CHAR_IS_WORD; + } + } + + // copy the default + char *ffs = ff->separators, *ffd = def, *ffe = &def[256]; + while(likely(ffd != ffe)) *ffs++ = *ffd++; + + // set the separators + if(unlikely(!separators)) separators = " \t=|"; + ffs = ff->separators; + const char *s = separators; + while(likely(*s)) ffs[(int)*s++] = PF_CHAR_IS_SEPARATOR; +} + +procfile *procfile_open(const char *filename, const char *separators, uint32_t flags) { + debug(D_PROCFILE, PF_PREFIX ": Opening file '%s'", filename); + + int fd = open(filename, O_RDONLY, 0666); + if(unlikely(fd == -1)) { + if(unlikely(!(flags & PROCFILE_FLAG_NO_ERROR_ON_FILE_IO))) error(PF_PREFIX ": Cannot open file '%s'", filename); + return NULL; + } + + size_t size = (unlikely(procfile_adaptive_initial_allocation)) ? procfile_max_allocation : PROCFILE_INCREMENT_BUFFER; + procfile *ff = malloc(sizeof(procfile) + size); + if(unlikely(!ff)) { + error(PF_PREFIX ": Cannot allocate memory for file '%s'", filename); + close(fd); + return NULL; + } + + strncpy(ff->filename, filename, FILENAME_MAX); + ff->filename[FILENAME_MAX] = '\0'; + + ff->fd = fd; + ff->size = size; + ff->len = 0; + ff->flags = flags; + + ff->lines = pflines_new(); + ff->words = pfwords_new(); + + if(unlikely(!ff->lines || !ff->words)) { + error(PF_PREFIX ": Cannot initialize parser for file '%s'", filename); + procfile_close(ff); + return NULL; + } + + procfile_set_separators(ff, separators); + + debug(D_PROCFILE, "File '%s' opened.", filename); + return ff; +} + +procfile *procfile_reopen(procfile *ff, const char *filename, const char *separators, uint32_t flags) { + if(unlikely(!ff)) return procfile_open(filename, separators, flags); + + if(likely(ff->fd != -1)) close(ff->fd); + + ff->fd = open(filename, O_RDONLY, 0666); + if(unlikely(ff->fd == -1)) { + procfile_close(ff); + return NULL; + } + + strncpy(ff->filename, filename, FILENAME_MAX); + ff->filename[FILENAME_MAX] = '\0'; + + ff->flags = flags; + + // do not do the separators again if NULL is given + if(likely(separators)) procfile_set_separators(ff, separators); + + return ff; +} + +// ---------------------------------------------------------------------------- +// example parsing of procfile data + +void procfile_print(procfile *ff) { + uint32_t lines = procfile_lines(ff), l; + uint32_t words, w; + char *s; + + debug(D_PROCFILE, "File '%s' with %d lines and %d words", ff->filename, ff->lines->len, ff->words->len); + + for(l = 0; likely(l < lines) ;l++) { + words = procfile_linewords(ff, l); + + debug(D_PROCFILE, " line %d starts at word %d and has %d words", l, ff->lines->lines[l].first, ff->lines->lines[l].words); + + for(w = 0; likely(w < words) ;w++) { + s = procfile_lineword(ff, l, w); + debug(D_PROCFILE, " [%d.%d] '%s'", l, w, s); + } + } +} |